Beam failure recovery procedure in carrier aggregation

ABSTRACT

A wireless device triggers transmission of a scheduling request (SR) based on triggering a beam failure recovery (BFR) of a secondary cell. A configured transmission of the SR based on transmitting a medium access control protocol data unit (MAC PDU) is stopped. The transmission comprises a BFR medium access control control element (BFR MAC CE) comprising information of the BFR triggered prior to assembling of the MAC PDU.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.62/842,306, filed May 2, 2019, which is hereby incorporated by referencein its entirety.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Examples of several of the various embodiments of the present disclosureare described herein with reference to the drawings.

FIG. 1 is a diagram of an example RAN architecture as per an aspect ofan embodiment of the present disclosure.

FIG. 2A is a diagram of an example user plane protocol stack as per anaspect of an embodiment of the present disclosure.

FIG. 2B is a diagram of an example control plane protocol stack as peran aspect of an embodiment of the present disclosure.

FIG. 3 is a diagram of an example wireless device and two base stationsas per an aspect of an embodiment of the present disclosure.

FIG. 4A, FIG. 4B, FIG. 4C and FIG. 4D are example diagrams for uplinkand downlink signal transmission as per an aspect of an embodiment ofthe present disclosure.

FIG. 5A is a diagram of an example uplink channel mapping and exampleuplink physical signals as per an aspect of an embodiment of the presentdisclosure.

FIG. 5B is a diagram of an example downlink channel mapping and exampledownlink physical signals as per an aspect of an embodiment of thepresent disclosure.

FIG. 6 is a diagram depicting an example transmission time or receptiontime for a carrier as per an aspect of an embodiment of the presentdisclosure.

FIG. 7A and FIG. 7B are diagrams depicting example sets of OFDMsubcarriers as per an aspect of an embodiment of the present disclosure.

FIG. 8 is a diagram depicting example OFDM radio resources as per anaspect of an embodiment of the present disclosure.

FIG. 9A is a diagram depicting an example CSI-RS and/or SS blocktransmission in a multi-beam system.

FIG. 9B is a diagram depicting an example downlink beam managementprocedure as per an aspect of an embodiment of the present disclosure.

FIG. 10 is an example diagram of configured BWPs as per an aspect of anembodiment of the present disclosure.

FIG. 11A, and FIG. 11B are diagrams of an example multi connectivity asper an aspect of an embodiment of the present disclosure.

FIG. 12 is a diagram of an example random access procedure as per anaspect of an embodiment of the present disclosure.

FIG. 13 is a structure of example MAC entities as per an aspect of anembodiment of the present disclosure.

FIG. 14 is a diagram of an example RAN architecture as per an aspect ofan embodiment of the present disclosure.

FIG. 15 is a diagram of example RRC states as per an aspect of anembodiment of the present disclosure.

FIG. 16A and FIG. 16B are examples of a downlink beam failure as per anaspect of an embodiment of the present disclosure.

FIG. 17 is an example flowchart of a downlink beam failure recoveryprocedure as per an aspect of an embodiment of the present disclosure.

FIG. 18 is an example of a downlink beam failure instance indication asper an aspect of an embodiment of the present disclosure.

FIG. 19 is an example of a downlink beam failure recovery procedure asper an aspect of an embodiment of the present disclosure.

FIG. 20 is an example of a downlink beam failure recovery procedure asper an aspect of an embodiment of the present disclosure.

FIG. 21 is an example flowchart of a downlink beam failure recoveryprocedure as per an aspect of an embodiment of the present disclosure.

FIG. 22A and FIG. 22B are examples of a configuration of a downlink beamfailure recovery procedure as per an aspect of an embodiment of thepresent disclosure.

FIG. 23 is an example of a downlink beam failure recovery procedure asper an aspect of an embodiment of the present disclosure.

FIG. 24 is an example flowchart of a downlink beam failure recoveryprocedure as per an aspect of an embodiment of the present disclosure.

FIG. 25 is an example of a downlink beam failure recovery procedure asper an aspect of an embodiment of the present disclosure.

FIG. 26 is an example of a downlink beam failure recovery procedure asper an aspect of an embodiment of the present disclosure.

FIG. 27 is an example flowchart of a downlink beam failure recoveryprocedure as per an aspect of an embodiment of the present disclosure.

FIG. 28 is an example of a downlink beam failure recovery procedure asper an aspect of an embodiment of the present disclosure.

FIG. 29 is an example flowchart of a downlink beam failure recoveryprocedure as per an aspect of an embodiment of the present disclosure.

FIG. 30 is an example of a downlink beam failure recovery procedure asper an aspect of an embodiment of the present disclosure.

FIG. 31 is an example of a downlink beam failure recovery procedure asper an aspect of an embodiment of the present disclosure.

FIG. 32 is a flow diagram of an aspect of an example embodiment of thepresent disclosure.

DETAILED DESCRIPTION OF EMBODIMENTS

Example embodiments of the present disclosure enable operation of beamfailure recovery procedure. Embodiments of the technology disclosedherein may be employed in the technical field of multicarriercommunication systems. More particularly, the embodiments of thetechnology disclosed herein may relate to beam failure recoveryprocedure in a multicarrier communication system.

The following Acronyms are used throughout the present disclosure:

-   -   3GPP 3rd Generation Partnership Project    -   5GC 5G Core Network    -   ACK Acknowledgement    -   AMF Access and Mobility Management Function    -   ARQ Automatic Repeat Request    -   AS Access Stratum    -   ASIC Application-Specific Integrated Circuit    -   BA Bandwidth Adaptation    -   BCCH Broadcast Control Channel    -   BCH Broadcast Channel    -   BPSK Binary Phase Shift Keying    -   BWP Bandwidth Part    -   CA Carrier Aggregation    -   CC Component Carrier    -   CCCH Common Control CHannel    -   CDMA Code Division Multiple Access    -   CN Core Network    -   CP Cyclic Prefix    -   CP-OFDM Cyclic Prefix-Orthogonal Frequency Division Multiplex    -   C-RNTI Cell-Radio Network Temporary Identifier    -   CS Configured Scheduling    -   CSI Channel State Information    -   CSI-RS Channel State Information-Reference Signal    -   CQI Channel Quality Indicator    -   CSS Common Search Space    -   CU Central Unit    -   DC Dual Connectivity    -   DCCH Dedicated Control Channel    -   DCI Downlink Control Information    -   DL Downlink    -   DL-SCH Downlink Shared CHannel    -   DM-RS DeModulation Reference Signal    -   DRB Data Radio Bearer    -   DRX Discontinuous Reception    -   DTCH Dedicated Traffic Channel    -   DU Distributed Unit    -   EPC Evolved Packet Core    -   E-UTRA Evolved UMTS Terrestrial Radio Access    -   E-UTRAN Evolved-Universal Terrestrial Radio Access Network    -   FDD Frequency Division Duplex    -   FPGA Field Programmable Gate Arrays    -   Fl-C Fl-Control plane    -   Fl-U Fl-User plane    -   gNB next generation Node B    -   HARQ Hybrid Automatic Repeat reQuest    -   HDL Hardware Description Languages    -   IE Information Element    -   IP Internet Protocol    -   LCID Logical Channel Identifier    -   LTE Long Term Evolution    -   MAC Media Access Control    -   MCG Master Cell Group    -   MCS Modulation and Coding Scheme    -   MeNB Master evolved Node B    -   MIB Master Information Block    -   MME Mobility Management Entity    -   MN Master Node    -   NACK Negative Acknowledgement    -   NAS Non-Access Stratum    -   NG CP Next Generation Control Plane    -   NGC Next Generation Core    -   NG-C NG-Control plane    -   ng-eNB next generation evolved Node B    -   NG-U NG-User plane    -   NR New Radio    -   NR MAC New Radio MAC    -   NR PDCP New Radio PDCP    -   NR PHY New Radio PHYsical    -   NR RLC New Radio RLC    -   NR RRC New Radio RRC    -   NS SAI Network Slice Selection Assistance Information    -   O&M Operation and Maintenance    -   OFDM orthogonal Frequency Division Multiplexing    -   PBCH Physical Broadcast CHannel    -   PCC Primary Component Carrier    -   PCCH Paging Control CHannel    -   PCell Primary Cell    -   PCH Paging CHannel    -   PDCCH Physical Downlink Control CHannel    -   PDCP Packet Data Convergence Protocol    -   PDSCH Physical Downlink Shared CHannel    -   PDU Protocol Data Unit    -   PHICH Physical HARQ Indicator CHannel    -   PHY PHYsical    -   PLMN Public Land Mobile Network    -   PMI Precoding Matrix Indicator    -   PRACH Physical Random Access CHannel    -   PRB Physical Resource Block    -   PSCell Primary Secondary Cell    -   PSS Primary Synchronization Signal    -   pTAG primary Timing Advance Group    -   PT-RS Phase Tracking Reference Signal    -   PUCCH Physical Uplink Control CHannel    -   PUSCH Physical Uplink Shared CHannel    -   QAM Quadrature Amplitude Modulation    -   QFI Quality of Service Indicator    -   QoS Quality of Service    -   QPSK Quadrature Phase Shift Keying    -   RA Random Access    -   RACH Random Access CHannel    -   RAN Radio Access Network    -   RAT Radio Access Technology    -   RA-RNTI Random Access-Radio Network Temporary Identifier    -   RB Resource Blocks    -   RBG Resource Block Groups    -   RI Rank indicator    -   RLC Radio Link Control    -   RLM Radio Link Monitoring    -   RRC Radio Resource Control    -   RS Reference Signal    -   RSRP Reference Signal Received Power    -   SCC Secondary Component Carrier    -   SCell Secondary Cell    -   SCG Secondary Cell Group    -   SC-FDMA Single Carrier-Frequency Division Multiple Access    -   SDAP Service Data Adaptation Protocol    -   SDU Service Data Unit    -   SeNB Secondary evolved Node B    -   SFN System Frame Number    -   S-GW Serving GateWay    -   SI System Information    -   SIB System Information Block    -   SMF Session Management Function    -   SN Secondary Node    -   SpCell Special Cell    -   SRB Signaling Radio Bearer    -   SRS Sounding Reference Signal    -   SS Synchronization Signal    -   SSS Secondary Synchronization Signal    -   sTAG secondary Timing Advance Group    -   TA Timing Advance    -   TAG Timing Advance Group    -   TAI Tracking Area Identifier    -   TAT Time Alignment Timer    -   TB Transport Block    -   TC-RNTI Temporary Cell-Radio Network Temporary Identifier    -   TDD Time Division Duplex    -   TDMA Time Division Multiple Access    -   TTI Transmission Time Interval    -   UCI Uplink Control Information    -   UE User Equipment    -   UL Uplink    -   UL-SCH Uplink Shared CHannel    -   UPF User Plane Function    -   UPGW User Plane Gateway    -   VHDL VHSIC Hardware Description Language    -   Xn-C Xn-Control plane    -   Xn-U Xn-User plane

Example embodiments of the disclosure may be implemented using variousphysical layer modulation and transmission mechanisms. Exampletransmission mechanisms may include, but are not limited to: CodeDivision Multiple Access (CDMA), Orthogonal Frequency Division MultipleAccess (OFDMA), Time Division Multiple Access (TDMA), Wavelettechnologies, and/or the like. Hybrid transmission mechanisms such asTDMA/CDMA, and OFDM/CDMA may also be employed. Various modulationschemes may be applied for signal transmission in the physical layer.Examples of modulation schemes include, but are not limited to: phase,amplitude, code, a combination of these, and/or the like. An exampleradio transmission method may implement Quadrature Amplitude Modulation(QAM) using Binary Phase Shift Keying (BPSK), Quadrature Phase ShiftKeying (QPSK), 16-QAM, 64-QAM, 256-QAM, 1024-QAM, and/or the like.Physical radio transmission may be enhanced by dynamically orsemi-dynamically changing the modulation and coding scheme depending ontransmission requirements and radio conditions.

FIG. 1 is an example Radio Access Network (RAN) architecture as per anaspect of an embodiment of the present disclosure. As illustrated inthis example, a RAN node may be a next generation Node B (gNB) (e.g.120A, 120B) providing New Radio (NR) user plane and control planeprotocol terminations towards a first wireless device (e.g. 110A). In anexample, a RAN node may be a next generation evolved Node B (ng-eNB)(e.g. 120C, 120D), providing Evolved UMTS Terrestrial Radio Access(E-UTRA) user plane and control plane protocol terminations towards asecond wireless device (e.g. 110B). The first wireless device maycommunicate with a gNB over a Uu interface. The second wireless devicemay communicate with a ng-eNB over a Uu interface.

A gNB or an ng-eNB may host functions such as radio resource managementand scheduling, IP header compression, encryption and integrityprotection of data, selection of Access and Mobility Management Function(AMF) at User Equipment (UE) attachment, routing of user plane andcontrol plane data, connection setup and release, scheduling andtransmission of paging messages (originated from the AMF), schedulingand transmission of system broadcast information (originated from theAMF or Operation and Maintenance (O&M)), measurement and measurementreporting configuration, transport level packet marking in the uplink,session management, support of network slicing, Quality of Service (QoS)flow management and mapping to data radio bearers, support of UEs inRRC_INACTIVE state, distribution function for Non-Access Stratum (NAS)messages, RAN sharing, dual connectivity or tight interworking betweenNR and E-UTRA.

In an example, one or more gNBs and/or one or more ng-eNBs may beinterconnected with each other by means of Xn interface. A gNB or anng-eNB may be connected by means of NG interfaces to 5G Core Network(5GC). In an example, 5GC may comprise one or more AMF/User PlanFunction (UPF) functions (e.g. 130A or 130B). A gNB or an ng-eNB may beconnected to a UPF by means of an NG-User plane (NG-U) interface. TheNG-U interface may provide delivery (e.g. non-guaranteed delivery) ofuser plane Protocol Data Units (PDUs) between a RAN node and the UPF. AgNB or an ng-eNB may be connected to an AMF by means of an NG-Controlplane (NG-C) interface. The NG-C interface may provide functions such asNG interface management, UE context management, UE mobility management,transport of NAS messages, paging, PDU session management, configurationtransfer or warning message transmission.

In an example, a UPF may host functions such as anchor point forintra-/inter-Radio Access Technology (RAT) mobility (when applicable),external PDU session point of interconnect to data network, packetrouting and forwarding, packet inspection and user plane part of policyrule enforcement, traffic usage reporting, uplink classifier to supportrouting traffic flows to a data network, branching point to supportmulti-homed PDU session, QoS handling for user plane, e.g. packetfiltering, gating, Uplink (UL)/Downlink (DL) rate enforcement, uplinktraffic verification (e.g. Service Data Flow (SDF) to QoS flow mapping),downlink packet buffering and/or downlink data notification triggering.

In an example, an AMF may host functions such as NAS signalingtermination, NAS signaling security, Access Stratum (AS) securitycontrol, inter Core Network (CN) node signaling for mobility between3^(rd) Generation Partnership Project (3GPP) access networks, idle modeUE reachability (e.g., control and execution of paging retransmission),registration area management, support of intra-system and inter-systemmobility, access authentication, access authorization including check ofroaming rights, mobility management control (subscription and policies),support of network slicing and/or Session Management Function (SMF)selection.

FIG. 2A is an example user plane protocol stack, where Service DataAdaptation Protocol (SDAP) (e.g. 211 and 221), Packet Data ConvergenceProtocol (PDCP) (e.g. 212 and 222), Radio Link Control (RLC) (e.g. 213and 223) and Media Access Control (MAC) (e.g. 214 and 224) sublayers andPhysical (PHY) (e.g. 215 and 225) layer may be terminated in wirelessdevice (e.g. 110) and gNB (e.g. 120) on the network side. In an example,a PHY layer provides transport services to higher layers (e.g. MAC, RRC,etc.). In an example, services and functions of a MAC sublayer maycomprise mapping between logical channels and transport channels,multiplexing/demultiplexing of MAC Service Data Units (SDUs) belongingto one or different logical channels into/from Transport Blocks (TBs)delivered to/from the PHY layer, scheduling information reporting, errorcorrection through Hybrid Automatic Repeat request (HARQ) (e.g. one HARQentity per carrier in case of Carrier Aggregation (CA)), priorityhandling between UEs by means of dynamic scheduling, priority handlingbetween logical channels of one UE by means of logical channelprioritization, and/or padding. A MAC entity may support one or multiplenumerologies and/or transmission timings. In an example, mappingrestrictions in a logical channel prioritization may control whichnumerology and/or transmission timing a logical channel may use. In anexample, an RLC sublayer may supports transparent mode (TM),unacknowledged mode (UM) and acknowledged mode (AM) transmission modes.The RLC configuration may be per logical channel with no dependency onnumerologies and/or Transmission Time Interval (TTI) durations. In anexample, Automatic Repeat Request (ARQ) may operate on any of thenumerologies and/or TTI durations the logical channel is configuredwith. In an example, services and functions of the PDCP layer for theuser plane may comprise sequence numbering, header compression anddecompression, transfer of user data, reordering and duplicatedetection, PDCP PDU routing (e.g. in case of split bearers),retransmission of PDCP SDUs, ciphering, deciphering and integrityprotection, PDCP SDU discard, PDCP re-establishment and data recoveryfor RLC AM, and/or duplication of PDCP PDUs. In an example, services andfunctions of SDAP may comprise mapping between a QoS flow and a dataradio bearer. In an example, services and functions of SDAP may comprisemapping Quality of Service Indicator (QFI) in DL and UL packets. In anexample, a protocol entity of SDAP may be configured for an individualPDU session.

FIG. 2B is an example control plane protocol stack where PDCP (e.g. 233and 242), RLC (e.g. 234 and 243) and MAC (e.g. 235 and 244) sublayersand PHY (e.g. 236 and 245) layer may be terminated in wireless device(e.g. 110) and gNB (e.g. 120) on a network side and perform service andfunctions described above. In an example, RRC (e.g. 232 and 241) may beterminated in a wireless device and a gNB on a network side. In anexample, services and functions of RRC may comprise broadcast of systeminformation related to AS and NAS, paging initiated by 5GC or RAN,establishment, maintenance and release of an RRC connection between theUE and RAN, security functions including key management, establishment,configuration, maintenance and release of Signaling Radio Bearers (SRBs)and Data Radio Bearers (DRBs), mobility functions, QoS managementfunctions, UE measurement reporting and control of the reporting,detection of and recovery from radio link failure, and/or NAS messagetransfer to/from NAS from/to a UE. In an example, NAS control protocol(e.g. 231 and 251) may be terminated in the wireless device and AMF(e.g. 130) on a network side and may perform functions such asauthentication, mobility management between a UE and a AMF for 3GPPaccess and non-3GPP access, and session management between a UE and aSMF for 3GPP access and non-3GPP access.

In an example, a base station may configure a plurality of logicalchannels for a wireless device. A logical channel in the plurality oflogical channels may correspond to a radio bearer and the radio bearermay be associated with a QoS requirement. In an example, a base stationmay configure a logical channel to be mapped to one or moreTTIs/numerologies in a plurality of TTIs/numerologies. The wirelessdevice may receive a Downlink Control Information (DCI) via PhysicalDownlink Control CHannel (PDCCH) indicating an uplink grant. In anexample, the uplink grant may be for a first TTI/numerology and mayindicate uplink resources for transmission of a transport block. Thebase station may configure each logical channel in the plurality oflogical channels with one or more parameters to be used by a logicalchannel prioritization procedure at the MAC layer of the wirelessdevice. The one or more parameters may comprise priority, prioritizedbit rate, etc. A logical channel in the plurality of logical channelsmay correspond to one or more buffers comprising data associated withthe logical channel. The logical channel prioritization procedure mayallocate the uplink resources to one or more first logical channels inthe plurality of logical channels and/or one or more MAC ControlElements (CEs). The one or more first logical channels may be mapped tothe first TTI/numerology. The MAC layer at the wireless device maymultiplex one or more MAC CEs and/or one or more MAC SDUs (e.g., logicalchannel) in a MAC PDU (e.g., transport block). In an example, the MACPDU may comprise a MAC header comprising a plurality of MAC sub-headers.A MAC sub-header in the plurality of MAC sub-headers may correspond to aMAC CE or a MAC SUD (logical channel) in the one or more MAC CEs and/orone or more MAC SDUs. In an example, a MAC CE or a logical channel maybe configured with a Logical Channel IDentifier (LCID). In an example,LCID for a logical channel or a MAC CE may be fixed/pre-configured. Inan example, LCID for a logical channel or MAC CE may be configured forthe wireless device by the base station. The MAC sub-headercorresponding to a MAC CE or a MAC SDU may comprise LCID associated withthe MAC CE or the MAC SDU.

In an example, a base station may activate and/or deactivate and/orimpact one or more processes (e.g., set values of one or more parametersof the one or more processes or start and/or stop one or more timers ofthe one or more processes) at the wireless device by employing one ormore MAC commands. The one or more MAC commands may comprise one or moreMAC control elements. In an example, the one or more processes maycomprise activation and/or deactivation of PDCP packet duplication forone or more radio bearers. The base station may transmit a MAC CEcomprising one or more fields, the values of the fields indicatingactivation and/or deactivation of PDCP duplication for the one or moreradio bearers. In an example, the one or more processes may compriseChannel State Information (CSI) transmission of on one or more cells.The base station may transmit one or more MAC CEs indicating activationand/or deactivation of the CSI transmission on the one or more cells. Inan example, the one or more processes may comprise activation ordeactivation of one or more secondary cells. In an example, the basestation may transmit a MA CE indicating activation or deactivation ofone or more secondary cells. In an example, the base station maytransmit one or more MAC CEs indicating starting and/or stopping one ormore Discontinuous Reception (DRX) timers at the wireless device. In anexample, the base station may transmit one or more MAC CEs indicatingone or more timing advance values for one or more Timing Advance Groups(TAGs).

FIG. 3 is a block diagram of base stations (base station 1, 120A, andbase station 2, 120B) and a wireless device 110. A wireless device maybe called a UE. A base station may be called a NB, eNB, gNB, and/orng-eNB. In an example, a wireless device and/or a base station may actas a relay node. The base station 1, 120A, may comprise at least onecommunication interface 320A (e.g. a wireless modem, an antenna, a wiredmodem, and/or the like), at least one processor 321A, and at least oneset of program code instructions 323A stored in non-transitory memory322A and executable by the at least one processor 321A. The base station2, 120B, may comprise at least one communication interface 320B, atleast one processor 321B, and at least one set of program codeinstructions 323B stored in non-transitory memory 322B and executable bythe at least one processor 321B.

A base station may comprise many sectors for example: 1, 2, 3, 4, or 6sectors. A base station may comprise many cells, for example, rangingfrom 1 to 50 cells or more. A cell may be categorized, for example, as aprimary cell or secondary cell. At Radio Resource Control (RRC)connection establishment/re-establishment/handover, one serving cell mayprovide the NAS (non-access stratum) mobility information (e.g. TrackingArea Identifier (TAI)). At RRC connection re-establishment/handover, oneserving cell may provide the security input. This cell may be referredto as the Primary Cell (PCell). In the downlink, a carrier correspondingto the PCell may be a DL Primary Component Carrier (PCC), while in theuplink, a carrier may be an UL PCC. Depending on wireless devicecapabilities, Secondary Cells (SCells) may be configured to formtogether with a PCell a set of serving cells. In a downlink, a carriercorresponding to an SCell may be a downlink secondary component carrier(DL SCC), while in an uplink, a carrier may be an uplink secondarycomponent carrier (UL SCC). An SCell may or may not have an uplinkcarrier.

A cell, comprising a downlink carrier and optionally an uplink carrier,may be assigned a physical cell ID and a cell index. A carrier (downlinkor uplink) may belong to one cell. The cell ID or cell index may alsoidentify the downlink carrier or uplink carrier of the cell (dependingon the context it is used). In the disclosure, a cell ID may be equallyreferred to a carrier ID, and a cell index may be referred to a carrierindex. In an implementation, a physical cell ID or a cell index may beassigned to a cell. A cell ID may be determined using a synchronizationsignal transmitted on a downlink carrier. A cell index may be determinedusing RRC messages. For example, when the disclosure refers to a firstphysical cell ID for a first downlink carrier, the disclosure may meanthe first physical cell ID is for a cell comprising the first downlinkcarrier. The same concept may apply to, for example, carrier activation.When the disclosure indicates that a first carrier is activated, thespecification may equally mean that a cell comprising the first carrieris activated.

A base station may transmit to a wireless device one or more messages(e.g. RRC messages) comprising a plurality of configuration parametersfor one or more cells. One or more cells may comprise at least oneprimary cell and at least one secondary cell. In an example, an RRCmessage may be broadcasted or unicasted to the wireless device. In anexample, configuration parameters may comprise common parameters anddedicated parameters.

Services and/or functions of an RRC sublayer may comprise at least oneof: broadcast of system information related to AS and NAS; paginginitiated by 5GC and/or NG-RAN; establishment, maintenance, and/orrelease of an RRC connection between a wireless device and NG-RAN, whichmay comprise at least one of addition, modification and release ofcarrier aggregation; or addition, modification, and/or release of dualconnectivity in NR or between E-UTRA and NR. Services and/or functionsof an RRC sublayer may further comprise at least one of securityfunctions comprising key management; establishment, configuration,maintenance, and/or release of Signaling Radio Bearers (SRBs) and/orData Radio Bearers (DRBs); mobility functions which may comprise atleast one of a handover (e.g. intra NR mobility or inter-RAT mobility)and a context transfer; or a wireless device cell selection andreselection and control of cell selection and reselection. Servicesand/or functions of an RRC sublayer may further comprise at least one ofQoS management functions; a wireless device measurementconfiguration/reporting; detection of and/or recovery from radio linkfailure; or NAS message transfer to/from a core network entity (e.g.AMF, Mobility Management Entity (MME)) from/to the wireless device.

An RRC sublayer may support an RRC_Idle state, an RRC_Inactive stateand/or an RRC_Connected state for a wireless device. In an RRC_Idlestate, a wireless device may perform at least one of: Public Land MobileNetwork (PLMN) selection; receiving broadcasted system information; cellselection/re-selection; monitoring/receiving a paging for mobileterminated data initiated by 5GC; paging for mobile terminated data areamanaged by 5GC; or DRX for CN paging configured via NAS. In anRRC_Inactive state, a wireless device may perform at least one of:receiving broadcasted system information; cell selection/re-selection;monitoring/receiving a RAN/CN paging initiated by NG-RAN/SGC; RAN-basednotification area (RNA) managed by NG-RAN; or DRX for RAN/CN pagingconfigured by NG-RAN/NAS. In an RRC_Idle state of a wireless device, abase station (e.g. NG-RAN) may keep a 5GC-NG-RAN connection (bothC/U-planes) for the wireless device; and/or store a UE AS context forthe wireless device. In an RRC_Connected state of a wireless device, abase station (e.g. NG-RAN) may perform at least one of: establishment of5GC-NG-RAN connection (both C/U-planes) for the wireless device; storinga UE AS context for the wireless device; transmit/receive of unicastdata to/from the wireless device; or network-controlled mobility basedon measurement results received from the wireless device. In anRRC_Connected state of a wireless device, an NG-RAN may know a cell thatthe wireless device belongs to.

System information (SI) may be divided into minimum SI and other SI. Theminimum SI may be periodically broadcast. The minimum SI may comprisebasic information required for initial access and information foracquiring any other SI broadcast periodically or provisioned on-demand,i.e. scheduling information. The other SI may either be broadcast, or beprovisioned in a dedicated manner, either triggered by a network or uponrequest from a wireless device. A minimum SI may be transmitted via twodifferent downlink channels using different messages (e.g.MasterInformationBlock and SystemInformationBlockType1). Another SI maybe transmitted via SystemInformationBlockType2. For a wireless device inan RRC_Connected state, dedicated RRC signalling may be employed for therequest and delivery of the other SI. For the wireless device in theRRC_Idle state and/or the RRC_Inactive state, the request may trigger arandom-access procedure.

A wireless device may report its radio access capability informationwhich may be static. A base station may request what capabilities for awireless device to report based on band information. When allowed by anetwork, a temporary capability restriction request may be sent by thewireless device to signal the limited availability of some capabilities(e.g. due to hardware sharing, interference or overheating) to the basestation. The base station may confirm or reject the request. Thetemporary capability restriction may be transparent to 5GC (e.g., staticcapabilities may be stored in 5GC).

When CA is configured, a wireless device may have an RRC connection witha network. At RRC connection establishment/re-establishment/handoverprocedure, one serving cell may provide NAS mobility information, and atRRC connection re-establishment/handover, one serving cell may provide asecurity input. This cell may be referred to as the PCell. Depending onthe capabilities of the wireless device, SCells may be configured toform together with the PCell a set of serving cells. The configured setof serving cells for the wireless device may comprise one PCell and oneor more SCells.

The reconfiguration, addition and removal of SCells may be performed byRRC. At intra-NR handover, RRC may also add, remove, or reconfigureSCells for usage with the target PCell. When adding a new SCell,dedicated RRC signalling may be employed to send all required systeminformation of the SCell i.e. while in connected mode, wireless devicesmay not need to acquire broadcasted system information directly from theSCells.

The purpose of an RRC connection reconfiguration procedure may be tomodify an RRC connection, (e.g. to establish, modify and/or release RBs,to perform handover, to setup, modify, and/or release measurements, toadd, modify, and/or release SCells and cell groups). As part of the RRCconnection reconfiguration procedure, NAS dedicated information may betransferred from the network to the wireless device. TheRRCConnectionReconfiguration message may be a command to modify an RRCconnection. It may convey information for measurement configuration,mobility control, radio resource configuration (e.g. RBs, MAC mainconfiguration and physical channel configuration) comprising anyassociated dedicated NAS information and security configuration. If thereceived RRC Connection Reconfiguration message includes thesCellToReleaseList, the wireless device may perform an SCell release. Ifthe received RRC Connection Reconfiguration message includes thesCellToAddModList, the wireless device may perform SCell additions ormodification.

An RRC connection establishment (or reestablishment, resume) proceduremay be to establish (or reestablish, resume) an RRC connection. an RRCconnection establishment procedure may comprise SRB1 establishment. TheRRC connection establishment procedure may be used to transfer theinitial NAS dedicated information/message from a wireless device toE-UTRAN. The RRCConnectionReestablishment message may be used tore-establish SRB1.

A measurement report procedure may be to transfer measurement resultsfrom a wireless device to NG-RAN. The wireless device may initiate ameasurement report procedure after successful security activation. Ameasurement report message may be employed to transmit measurementresults.

The wireless device 110 may comprise at least one communicationinterface 310 (e.g. a wireless modem, an antenna, and/or the like), atleast one processor 314, and at least one set of program codeinstructions 316 stored in non-transitory memory 315 and executable bythe at least one processor 314. The wireless device 110 may furthercomprise at least one of at least one speaker/microphone 311, at leastone keypad 312, at least one display/touchpad 313, at least one powersource 317, at least one global positioning system (GPS) chipset 318,and other peripherals 319.

The processor 314 of the wireless device 110, the processor 321A of thebase station 1 120A, and/or the processor 321B of the base station 2120B may comprise at least one of a general-purpose processor, a digitalsignal processor (DSP), a controller, a microcontroller, an applicationspecific integrated circuit (ASIC), a field programmable gate array(FPGA) and/or other programmable logic device, discrete gate and/ortransistor logic, discrete hardware components, and the like. Theprocessor 314 of the wireless device 110, the processor 321A in basestation 1 120A, and/or the processor 321B in base station 2 120B mayperform at least one of signal coding/processing, data processing, powercontrol, input/output processing, and/or any other functionality thatmay enable the wireless device 110, the base station 1 120A and/or thebase station 2 120B to operate in a wireless environment.

The processor 314 of the wireless device 110 may be connected to thespeaker/microphone 311, the keypad 312, and/or the display/touchpad 313.The processor 314 may receive user input data from and/or provide useroutput data to the speaker/microphone 311, the keypad 312, and/or thedisplay/touchpad 313. The processor 314 in the wireless device 110 mayreceive power from the power source 317 and/or may be configured todistribute the power to the other components in the wireless device 110.The power source 317 may comprise at least one of one or more dry cellbatteries, solar cells, fuel cells, and the like. The processor 314 maybe connected to the GPS chipset 318. The GPS chipset 318 may beconfigured to provide geographic location information of the wirelessdevice 110.

The processor 314 of the wireless device 110 may further be connected toother peripherals 319, which may comprise one or more software and/orhardware modules that provide additional features and/orfunctionalities. For example, the peripherals 319 may comprise at leastone of an accelerometer, a satellite transceiver, a digital camera, auniversal serial bus (USB) port, a hands-free headset, a frequencymodulated (FM) radio unit, a media player, an Internet browser, and thelike.

The communication interface 320A of the base station 1, 120A, and/or thecommunication interface 320B of the base station 2, 120B, may beconfigured to communicate with the communication interface 310 of thewireless device 110 via a wireless link 330A and/or a wireless link 330Brespectively. In an example, the communication interface 320A of thebase station 1, 120A, may communicate with the communication interface320B of the base station 2 and other RAN and core network nodes.

The wireless link 330A and/or the wireless link 330B may comprise atleast one of a bi-directional link and/or a directional link. Thecommunication interface 310 of the wireless device 110 may be configuredto communicate with the communication interface 320A of the base station1 120A and/or with the communication interface 320B of the base station2 120B. The base station 1 120A and the wireless device 110 and/or thebase station 2 120B and the wireless device 110 may be configured tosend and receive transport blocks via the wireless link 330A and/or viathe wireless link 330B, respectively. The wireless link 330A and/or thewireless link 330B may employ at least one frequency carrier. Accordingto some of various aspects of embodiments, transceiver(s) may beemployed. A transceiver may be a device that comprises both atransmitter and a receiver. Transceivers may be employed in devices suchas wireless devices, base stations, relay nodes, and/or the like.Example embodiments for radio technology implemented in thecommunication interface 310, 320A, 320B and the wireless link 330A, 330Bare illustrated in FIG. 4A, FIG. 4B, FIG. 4C, FIG. 4D, FIG. 6, FIG. 7A,FIG. 7B, FIG. 8, and associated text.

In an example, other nodes in a wireless network (e.g. AMF, UPF, SMF,etc.) may comprise one or more communication interfaces, one or moreprocessors, and memory storing instructions.

A node (e.g. wireless device, base station, AMF, SMF, UPF, servers,switches, antennas, and/or the like) may comprise one or moreprocessors, and memory storing instructions that when executed by theone or more processors causes the node to perform certain processesand/or functions. Example embodiments may enable operation ofsingle-carrier and/or multi-carrier communications. Other exampleembodiments may comprise a non-transitory tangible computer readablemedia comprising instructions executable by one or more processors tocause operation of single-carrier and/or multi-carrier communications.Yet other example embodiments may comprise an article of manufacturethat comprises a non-transitory tangible computer readablemachine-accessible medium having instructions encoded thereon forenabling programmable hardware to cause a node to enable operation ofsingle-carrier and/or multi-carrier communications. The node may includeprocessors, memory, interfaces, and/or the like.

An interface may comprise at least one of a hardware interface, afirmware interface, a software interface, and/or a combination thereof.The hardware interface may comprise connectors, wires, electronicdevices such as drivers, amplifiers, and/or the like. The softwareinterface may comprise code stored in a memory device to implementprotocol(s), protocol layers, communication drivers, device drivers,combinations thereof, and/or the like. The firmware interface maycomprise a combination of embedded hardware and code stored in and/or incommunication with a memory device to implement connections, electronicdevice operations, protocol(s), protocol layers, communication drivers,device drivers, hardware operations, combinations thereof, and/or thelike.

FIG. 4A, FIG. 4B, FIG. 4C and FIG. 4D are example diagrams for uplinkand downlink signal transmission as per an aspect of an embodiment ofthe present disclosure. FIG. 4A shows an example uplink transmitter forat least one physical channel A baseband signal representing a physicaluplink shared channel may perform one or more functions. The one or morefunctions may comprise at least one of: scrambling; modulation ofscrambled bits to generate complex-valued symbols; mapping of thecomplex-valued modulation symbols onto one or several transmissionlayers; transform precoding to generate complex-valued symbols;precoding of the complex-valued symbols; mapping of precodedcomplex-valued symbols to resource elements; generation ofcomplex-valued time-domain Single Carrier-Frequency Division MultipleAccess (SC-FDMA) or CP-OFDM signal for an antenna port; and/or the like.In an example, when transform precoding is enabled, a SC-1-DMA signalfor uplink transmission may be generated. In an example, when transformprecoding is not enabled, an CP-OFDM signal for uplink transmission maybe generated by FIG. 4A. These functions are illustrated as examples andit is anticipated that other mechanisms may be implemented in variousembodiments.

An example structure for modulation and up-conversion to the carrierfrequency of the complex-valued SC-FDMA or CP-OFDM baseband signal foran antenna port and/or the complex-valued Physical Random Access CHannel(PRACH) baseband signal is shown in FIG. 4B. Filtering may be employedprior to transmission.

An example structure for downlink transmissions is shown in FIG. 4C. Thebaseband signal representing a downlink physical channel may perform oneor more functions. The one or more functions may comprise: scrambling ofcoded bits in a codeword to be transmitted on a physical channel;modulation of scrambled bits to generate complex-valued modulationsymbols; mapping of the complex-valued modulation symbols onto one orseveral transmission layers; precoding of the complex-valued modulationsymbols on a layer for transmission on the antenna ports; mapping ofcomplex-valued modulation symbols for an antenna port to resourceelements; generation of complex-valued time-domain OFDM signal for anantenna port; and/or the like. These functions are illustrated asexamples and it is anticipated that other mechanisms may be implementedin various embodiments.

In an example, a gNB may transmit a first symbol and a second symbol onan antenna port, to a wireless device. The wireless device may infer thechannel (e.g., fading gain, multipath delay, etc.) for conveying thesecond symbol on the antenna port, from the channel for conveying thefirst symbol on the antenna port. In an example, a first antenna portand a second antenna port may be quasi co-located if one or morelarge-scale properties of the channel over which a first symbol on thefirst antenna port is conveyed may be inferred from the channel overwhich a second symbol on a second antenna port is conveyed. The one ormore large-scale properties may comprise at least one of: delay spread;doppler spread; doppler shift; average gain; average delay; and/orspatial Receiving (Rx) parameters.

An example modulation and up-conversion to the carrier frequency of thecomplex-valued OFDM baseband signal for an antenna port is shown in FIG.4D. Filtering may be employed prior to transmission.

FIG. 5A is a diagram of an example uplink channel mapping and exampleuplink physical signals. FIG. 5B is a diagram of an example downlinkchannel mapping and a downlink physical signals. In an example, aphysical layer may provide one or more information transfer services toa MAC and/or one or more higher layers. For example, the physical layermay provide the one or more information transfer services to the MAC viaone or more transport channels. An information transfer service mayindicate how and with what characteristics data are transferred over theradio interface.

In an example embodiment, a radio network may comprise one or moredownlink and/or uplink transport channels. For example, a diagram inFIG. 5A shows example uplink transport channels comprising Uplink-SharedCHannel (UL-SCH) 501 and Random Access CHannel (RACH) 502. A diagram inFIG. 5B shows example downlink transport channels comprisingDownlink-Shared CHannel (DL-SCH) 511, Paging CHannel (PCH) 512, andBroadcast CHannel (BCH) 513. A transport channel may be mapped to one ormore corresponding physical channels. For example, UL-SCH 501 may bemapped to Physical Uplink Shared CHannel (PUSCH) 503. RACH 502 may bemapped to PRACH 505. DL-SCH 511 and PCH 512 may be mapped to PhysicalDownlink Shared CHannel (PDSCH) 514. BCH 513 may be mapped to PhysicalBroadcast CHannel (PBCH) 516.

There may be one or more physical channels without a correspondingtransport channel. The one or more physical channels may be employed forUplink Control Information (UCI) 509 and/or Downlink Control Information(DCI) 517. For example, Physical Uplink Control CHannel (PUCCH) 504 maycarry UCI 509 from a UE to a base station. For example, PhysicalDownlink Control CHannel (PDCCH) 515 may carry DCI 517 from a basestation to a UE. NR may support UCI 509 multiplexing in PUSCH 503 whenUCI 509 and PUSCH 503 transmissions may coincide in a slot at least inpart. The UCI 509 may comprise at least one of CSI, Acknowledgement(ACK)/Negative Acknowledgement (NACK), and/or scheduling request. TheDCI 517 on PDCCH 515 may indicate at least one of following: one or moredownlink assignments and/or one or more uplink scheduling grants

In uplink, a UE may transmit one or more Reference Signals (RSs) to abase station. For example, the one or more RSs may be at least one ofDemodulation-RS (DM-RS) 506, Phase Tracking-RS (PT-RS) 507, and/orSounding RS (SRS) 508. In downlink, a base station may transmit (e.g.,unicast, multicast, and/or broadcast) one or more RSs to a UE. Forexample, the one or more RSs may be at least one of PrimarySynchronization Signal (PSS)/Secondary Synchronization Signal (SSS) 521,CSI-RS 522, DM-RS 523, and/or PT-RS 524.

In an example, a UE may transmit one or more uplink DM-RSs 506 to a basestation for channel estimation, for example, for coherent demodulationof one or more uplink physical channels (e.g., PUSCH 503 and/or PUCCH504). For example, a UE may transmit a base station at least one uplinkDM-RS 506 with PUSCH 503 and/or PUCCH 504, wherein the at least oneuplink DM-RS 506 may be spanning a same frequency range as acorresponding physical channel. In an example, a base station mayconfigure a UE with one or more uplink DM-RS configurations. At leastone DM-RS configuration may support a front-loaded DM-RS pattern. Afront-loaded DM-RS may be mapped over one or more OFDM symbols (e.g., 1or 2 adjacent OFDM symbols). One or more additional uplink DM-RS may beconfigured to transmit at one or more symbols of a PUSCH and/or PUCCH. Abase station may semi-statistically configure a UE with a maximum numberof front-loaded DM-RS symbols for PUSCH and/or PUCCH. For example, a UEmay schedule a single-symbol DM-RS and/or double symbol DM-RS based on amaximum number of front-loaded DM-RS symbols, wherein a base station mayconfigure the UE with one or more additional uplink DM-RS for PUSCHand/or PUCCH. A new radio network may support, e.g., at least forCP-OFDM, a common DM-RS structure for DL and UL, wherein a DM-RSlocation, DM-RS pattern, and/or scrambling sequence may be same ordifferent.

In an example, whether uplink PT-RS 507 is present or not may depend ona RRC configuration. For example, a presence of uplink PT-RS may beUE-specifically configured. For example, a presence and/or a pattern ofuplink PT-RS 507 in a scheduled resource may be UE-specificallyconfigured by a combination of RRC signaling and/or association with oneor more parameters employed for other purposes (e.g., Modulation andCoding Scheme (MCS)) which may be indicated by DCI. When configured, adynamic presence of uplink PT-RS 507 may be associated with one or moreDCI parameters comprising at least MCS. A radio network may supportplurality of uplink PT-RS densities defined in time/frequency domain.When present, a frequency domain density may be associated with at leastone configuration of a scheduled bandwidth. A UE may assume a sameprecoding for a DMRS port and a PT-RS port. A number of PT-RS ports maybe fewer than a number of DM-RS ports in a scheduled resource. Forexample, uplink PT-RS 507 may be confined in the scheduledtime/frequency duration for a UE.

In an example, a UE may transmit SRS 508 to a base station for channelstate estimation to support uplink channel dependent scheduling and/orlink adaptation. For example, SRS 508 transmitted by a UE may allow fora base station to estimate an uplink channel state at one or moredifferent frequencies. A base station scheduler may employ an uplinkchannel state to assign one or more resource blocks of good quality foran uplink PUSCH transmission from a UE. A base station maysemi-statistically configure a UE with one or more SRS resource sets.For an SRS resource set, a base station may configure a UE with one ormore SRS resources. An SRS resource set applicability may be configuredby a higher layer (e.g., RRC) parameter. For example, when a higherlayer parameter indicates beam management, a SRS resource in each of oneor more SRS resource sets may be transmitted at a time instant. A UE maytransmit one or more SRS resources in different SRS resource setssimultaneously. A new radio network may support aperiodic, periodicand/or semi-persistent SRS transmissions. A UE may transmit SRSresources based on one or more trigger types, wherein the one or moretrigger types may comprise higher layer signaling (e.g., RRC) and/or oneor more DCI formats (e.g., at least one DCI format may be employed for aUE to select at least one of one or more configured SRS resource sets.An SRS trigger type 0 may refer to an SRS triggered based on a higherlayer signaling. An SRS trigger type 1 may refer to an SRS triggeredbased on one or more DCI formats. In an example, when PUSCH 503 and SRS508 are transmitted in a same slot, a UE may be configured to transmitSRS 508 after a transmission of PUSCH 503 and corresponding uplink DM-RS506.

In an example, a base station may semi-statistically configure a UE withone or more SRS configuration parameters indicating at least one offollowing: a SRS resource configuration identifier, a number of SRSports, time domain behavior of SRS resource configuration (e.g., anindication of periodic, semi-persistent, or aperiodic SRS), slot(mini-slot, and/or subframe) level periodicity and/or offset for aperiodic and/or aperiodic SRS resource, a number of OFDM symbols in aSRS resource, starting OFDM symbol of a SRS resource, a SRS bandwidth, afrequency hopping bandwidth, a cyclic shift, and/or a SRS sequence ID.

In an example, in a time domain, an SS/PBCH block may comprise one ormore OFDM symbols (e.g., 4 OFDM symbols numbered in increasing orderfrom 0 to 3) within the SS/PBCH block. An SS/PBCH block may comprisePSS/SSS 521 and PBCH 516. In an example, in the frequency domain, anSS/PBCH block may comprise one or more contiguous subcarriers (e.g., 240contiguous subcarriers with the subcarriers numbered in increasing orderfrom 0 to 239) within the SS/PBCH block. For example, a PSS/SSS 521 mayoccupy 1 OFDM symbol and 127 subcarriers. For example, PBCH 516 may spanacross 3 OFDM symbols and 240 subcarriers. A UE may assume that one ormore SS/PBCH blocks transmitted with a same block index may be quasico-located, e.g., with respect to Doppler spread, Doppler shift, averagegain, average delay, and spatial Rx parameters. A UE may not assumequasi co-location for other SS/PBCH block transmissions. A periodicityof an SS/PBCH block may be configured by a radio network (e.g., by anRRC signaling) and one or more time locations where the SS/PBCH blockmay be sent may be determined by sub-carrier spacing. In an example, aUE may assume a band-specific sub-carrier spacing for an SS/PBCH blockunless a radio network has configured a UE to assume a differentsub-carrier spacing.

In an example, downlink CSI-RS 522 may be employed for a UE to acquirechannel state information. A radio network may support periodic,aperiodic, and/or semi-persistent transmission of downlink CSI-RS 522.For example, a base station may semi-statistically configure and/orreconfigure a UE with periodic transmission of downlink CSI-RS 522. Aconfigured CSI-RS resources may be activated ad/or deactivated. Forsemi-persistent transmission, an activation and/or deactivation ofCSI-RS resource may be triggered dynamically. In an example, CSI-RSconfiguration may comprise one or more parameters indicating at least anumber of antenna ports. For example, a base station may configure a UEwith 32 ports. A base station may semi-statistically configure a UE withone or more CSI-RS resource sets. One or more CSI-RS resources may beallocated from one or more CSI-RS resource sets to one or more UEs. Forexample, a base station may semi-statistically configure one or moreparameters indicating CSI RS resource mapping, for example, time-domainlocation of one or more CSI-RS resources, a bandwidth of a CSI-RSresource, and/or a periodicity. In an example, a UE may be configured toemploy a same OFDM symbols for downlink CSI-RS 522 and control resourceset (coreset) when the downlink CSI-RS 522 and coreset are spatiallyquasi co-located and resource elements associated with the downlinkCSI-RS 522 are the outside of PRBs configured for coreset. In anexample, a UE may be configured to employ a same OFDM symbols fordownlink CSI-RS 522 and SS/PBCH blocks when the downlink CSI-RS 522 andSS/PBCH blocks are spatially quasi co-located and resource elementsassociated with the downlink CSI-RS 522 are the outside of PRBsconfigured for SS/PBCH blocks.

In an example, a UE may transmit one or more downlink DM-RSs 523 to abase station for channel estimation, for example, for coherentdemodulation of one or more downlink physical channels (e.g., PDSCH514). For example, a radio network may support one or more variableand/or configurable DM-RS patterns for data demodulation. At least onedownlink DM-RS configuration may support a front-loaded DM-RS pattern. Afront-loaded DM-RS may be mapped over one or more OFDM symbols (e.g., 1or 2 adjacent OFDM symbols). A base station may semi-statisticallyconfigure a UE with a maximum number of front-loaded DM-RS symbols forPDSCH 514. For example, a DM-RS configuration may support one or moreDM-RS ports. For example, for single user-MIMO, a DM-RS configurationmay support at least 8 orthogonal downlink DM-RS ports. For example, formultiuser-MIMO, a DM-RS configuration may support 12 orthogonal downlinkDM-RS ports. A radio network may support, e.g., at least for CP-OFDM, acommon DM-RS structure for DL and UL, wherein a DM-RS location, DM-RSpattern, and/or scrambling sequence may be same or different.

In an example, whether downlink PT-RS 524 is present or not may dependon a RRC configuration. For example, a presence of downlink PT-RS 524may be UE-specifically configured. For example, a presence and/or apattern of downlink PT-RS 524 in a scheduled resource may beUE-specifically configured by a combination of RRC signaling and/orassociation with one or more parameters employed for other purposes(e.g., MCS) which may be indicated by DCI. When configured, a dynamicpresence of downlink PT-RS 524 may be associated with one or more DCIparameters comprising at least MCS. A radio network may supportplurality of PT-RS densities defined in time/frequency domain. Whenpresent, a frequency domain density may be associated with at least oneconfiguration of a scheduled bandwidth. A UE may assume a same precodingfor a DMRS port and a PT-RS port. A number of PT-RS ports may be fewerthan a number of DM-RS ports in a scheduled resource. For example,downlink PT-RS 524 may be confined in the scheduled time/frequencyduration for a UE.

FIG. 6 is a diagram depicting an example transmission time and receptiontime for a carrier as per an aspect of an embodiment of the presentdisclosure. A multicarrier OFDM communication system may include one ormore carriers, for example, ranging from 1 to 32 carriers, in case ofcarrier aggregation, or ranging from 1 to 64 carriers, in case of dualconnectivity. Different radio frame structures may be supported (e.g.,for FDD and for TDD duplex mechanisms). FIG. 6 shows an example frametiming. Downlink and uplink transmissions may be organized into radioframes 601. In this example, radio frame duration is 10 ms. In thisexample, a 10 ms radio frame 601 may be divided into ten equally sizedsubframes 602 with 1 ms duration. Subframe(s) may comprise one or moreslots (e.g. slots 603 and 605) depending on subcarrier spacing and/or CPlength. For example, a subframe with 15 kHz, 30 kHz, 60 kHz, 120 kHz,240 kHz and 480 kHz subcarrier spacing may comprise one, two, four,eight, sixteen and thirty-two slots, respectively. In FIG. 6, a subframemay be divided into two equally sized slots 603 with 0.5 ms duration.For example, 10 subframes may be available for downlink transmission and10 subframes may be available for uplink transmissions in a 10 msinterval. Uplink and downlink transmissions may be separated in thefrequency domain. Slot(s) may include a plurality of OFDM symbols 604.The number of OFDM symbols 604 in a slot 605 may depend on the cyclicprefix length. For example, a slot may be 14 OFDM symbols for the samesubcarrier spacing of up to 480 kHz with normal CP. A slot may be 12OFDM symbols for the same subcarrier spacing of 60 kHz with extended CP.A slot may contain downlink, uplink, or a downlink part and an uplinkpart and/or alike.

FIG. 7A is a diagram depicting example sets of OFDM subcarriers as peran aspect of an embodiment of the present disclosure. In the example, agNB may communicate with a wireless device with a carrier with anexample channel bandwidth 700. Arrow(s) in the diagram may depict asubcarrier in a multicarrier OFDM system. The OFDM system may usetechnology such as OFDM technology, SC-FDMA technology, and/or the like.In an example, an arrow 701 shows a subcarrier transmitting informationsymbols. In an example, a subcarrier spacing 702, between two contiguoussubcarriers in a carrier, may be any one of 15 KHz, 30 KHz, 60 KHz, 120KHz, 240 KHz etc. In an example, different subcarrier spacing maycorrespond to different transmission numerologies. In an example, atransmission numerology may comprise at least: a numerology index; avalue of subcarrier spacing; a type of cyclic prefix (CP). In anexample, a gNB may transmit to/receive from a UE on a number ofsubcarriers 703 in a carrier. In an example, a bandwidth occupied by anumber of subcarriers 703 (transmission bandwidth) may be smaller thanthe channel bandwidth 700 of a carrier, due to guard band 704 and 705.In an example, a guard band 704 and 705 may be used to reduceinterference to and from one or more neighbor carriers. A number ofsubcarriers (transmission bandwidth) in a carrier may depend on thechannel bandwidth of the carrier and the subcarrier spacing. Forexample, a transmission bandwidth, for a carrier with 20 MHz channelbandwidth and 15 KHz subcarrier spacing, may be in number of 1024subcarriers.

In an example, a gNB and a wireless device may communicate with multipleCCs when configured with CA. In an example, different component carriersmay have different bandwidth and/or subcarrier spacing, if CA issupported. In an example, a gNB may transmit a first type of service toa UE on a first component carrier. The gNB may transmit a second type ofservice to the UE on a second component carrier. Different type ofservices may have different service requirement (e.g., data rate,latency, reliability), which may be suitable for transmission viadifferent component carrier having different subcarrier spacing and/orbandwidth. FIG. 7B shows an example embodiment. A first componentcarrier may comprise a first number of subcarriers 706 with a firstsubcarrier spacing 709. A second component carrier may comprise a secondnumber of subcarriers 707 with a second subcarrier spacing 710. A thirdcomponent carrier may comprise a third number of subcarriers 708 with athird subcarrier spacing 711. Carriers in a multicarrier OFDMcommunication system may be contiguous carriers, non-contiguouscarriers, or a combination of both contiguous and non-contiguouscarriers.

FIG. 8 is a diagram depicting OFDM radio resources as per an aspect ofan embodiment of the present disclosure. In an example, a carrier mayhave a transmission bandwidth 801. In an example, a resource grid may bein a structure of frequency domain 802 and time domain 803. In anexample, a resource grid may comprise a first number of OFDM symbols ina subframe and a second number of resource blocks, starting from acommon resource block indicated by higher-layer signaling (e.g. RRCsignaling), for a transmission numerology and a carrier. In an example,in a resource grid, a resource unit identified by a subcarrier index anda symbol index may be a resource element 805. In an example, a subframemay comprise a first number of OFDM symbols 807 depending on anumerology associated with a carrier. For example, when a subcarrierspacing of a numerology of a carrier is 15 KHz, a subframe may have 14OFDM symbols for a carrier. When a subcarrier spacing of a numerology is30 KHz, a subframe may have 28 OFDM symbols. When a subcarrier spacingof a numerology is 60 Khz, a subframe may have 56 OFDM symbols, etc. Inan example, a second number of resource blocks comprised in a resourcegrid of a carrier may depend on a bandwidth and a numerology of thecarrier.

As shown in FIG. 8, a resource block 806 may comprise 12 subcarriers. Inan example, multiple resource blocks may be grouped into a ResourceBlock Group (RBG) 804. In an example, a size of a RBG may depend on atleast one of: a RRC message indicating a RBG size configuration; a sizeof a carrier bandwidth; or a size of a bandwidth part of a carrier. Inan example, a carrier may comprise multiple bandwidth parts. A firstbandwidth part of a carrier may have different frequency location and/orbandwidth from a second bandwidth part of the carrier.

In an example, a gNB may transmit a downlink control informationcomprising a downlink or uplink resource block assignment to a wirelessdevice. A base station may transmit to or receive from, a wirelessdevice, data packets (e.g. transport blocks) scheduled and transmittedvia one or more resource blocks and one or more slots according toparameters in a downlink control information and/or RRC message(s). Inan example, a starting symbol relative to a first slot of the one ormore slots may be indicated to the wireless device. In an example, a gNBmay transmit to or receive from, a wireless device, data packetsscheduled on one or more RBGs and one or more slots.

In an example, a gNB may transmit a downlink control informationcomprising a downlink assignment to a wireless device via one or morePDCCHs. The downlink assignment may comprise parameters indicating atleast modulation and coding format; resource allocation; and/or HARQinformation related to DL-SCH. In an example, a resource allocation maycomprise parameters of resource block allocation; and/or slotallocation. In an example, a gNB may dynamically allocate resources to awireless device via a Cell-Radio Network Temporary Identifier (C-RNTI)on one or more PDCCHs. The wireless device may monitor the one or morePDCCHs in order to find possible allocation when its downlink receptionis enabled. The wireless device may receive one or more downlink datapackage on one or more PDSCH scheduled by the one or more PDCCHs, whensuccessfully detecting the one or more PDCCHs.

In an example, a gNB may allocate Configured Scheduling (CS) resourcesfor down link transmission to a wireless device. The gNB may transmitone or more RRC messages indicating a periodicity of the CS grant. ThegNB may transmit a DCI via a PDCCH addressed to a ConfiguredScheduling-RNTI (CS-RNTI) activating the CS resources. The DCI maycomprise parameters indicating that the downlink grant is a CS grant.The CS grant may be implicitly reused according to the periodicitydefined by the one or more RRC messages, until deactivated.

In an example, a gNB may transmit a downlink control informationcomprising an uplink grant to a wireless device via one or more PDCCHs.The uplink grant may comprise parameters indicating at least modulationand coding format; resource allocation; and/or HARQ information relatedto UL-SCH. In an example, a resource allocation may comprise parametersof resource block allocation; and/or slot allocation. In an example, agNB may dynamically allocate resources to a wireless device via a C-RNTIon one or more PDCCHs. The wireless device may monitor the one or morePDCCHs in order to find possible resource allocation. The wirelessdevice may transmit one or more uplink data package via one or morePUSCH scheduled by the one or more PDCCHs, when successfully detectingthe one or more PDCCHs.

In an example, a gNB may allocate CS resources for uplink datatransmission to a wireless device. The gNB may transmit one or more RRCmessages indicating a periodicity of the CS grant. The gNB may transmita DCI via a PDCCH addressed to a CS-RNTI activating the CS resources.The DCI may comprise parameters indicating that the uplink grant is a CSgrant. The CS grant may be implicitly reused according to theperiodicity defined by the one or more RRC message, until deactivated.

In an example, a base station may transmit DCI/control signaling viaPDCCH. The DCI may take a format in a plurality of formats. A DCI maycomprise downlink and/or uplink scheduling information (e.g., resourceallocation information, HARQ related parameters, MCS), request for CSI(e.g., aperiodic CQI reports), request for SRS, uplink power controlcommands for one or more cells, one or more timing information (e.g., TBtransmission/reception timing, HARQ feedback timing, etc.), etc. In anexample, a DCI may indicate an uplink grant comprising transmissionparameters for one or more transport blocks. In an example, a DCI mayindicate downlink assignment indicating parameters for receiving one ormore transport blocks. In an example, a DCI may be used by base stationto initiate a contention-free random access at the wireless device. Inan example, the base station may transmit a DCI comprising slot formatindicator (SFI) notifying a slot format. In an example, the base stationmay transmit a DCI comprising pre-emption indication notifying thePRB(s) and/or OFDM symbol(s) where a UE may assume no transmission isintended for the UE. In an example, the base station may transmit a DCIfor group power control of PUCCH or PUSCH or SRS. In an example, a DCImay correspond to an RNTI. In an example, the wireless device may obtainan RNTI in response to completing the initial access (e.g., C-RNTI). Inan example, the base station may configure an RNTI for the wireless(e.g., CS-RNTI, TPC-CS-RNTI, TPC-PUCCH-RNTI, TPC-PUSCH-RNTI,TPC-SRS-RNTI). In an example, the wireless device may compute an RNTI(e.g., the wireless device may compute RA-RNTI based on resources usedfor transmission of a preamble). In an example, an RNTI may have apre-configured value (e.g., P-RNTI or SI-RNTI). In an example, awireless device may monitor a group common search space which may beused by base station for transmitting DCIs that are intended for a groupof UEs. In an example, a group common DCI may correspond to an RNTIwhich is commonly configured for a group of UEs. In an example, awireless device may monitor a UE-specific search space. In an example, aUE specific DCI may correspond to an RNTI configured for the wirelessdevice.

A NR system may support a single beam operation and/or a multi-beamoperation. In a multi-beam operation, a base station may perform adownlink beam sweeping to provide coverage for common control channelsand/or downlink SS blocks, which may comprise at least a PSS, a SSS,and/or PBCH. A wireless device may measure quality of a beam pair linkusing one or more RSs. One or more SS blocks, or one or more CSI-RSresources, associated with a CSI-RS resource index (CRI), or one or moreDM-RSs of PBCH, may be used as RS for measuring quality of a beam pairlink. Quality of a beam pair link may be defined as a reference signalreceived power (RSRP) value, or a reference signal received quality(RSRQ) value, and/or a CSI value measured on RS resources. The basestation may indicate whether an RS resource, used for measuring a beampair link quality, is quasi-co-located (QCLed) with DM-RSs of a controlchannel. A RS resource and DM-RSs of a control channel may be calledQCLed when a channel characteristics from a transmission on an RS to awireless device, and that from a transmission on a control channel to awireless device, are similar or same under a configured criterion. In amulti-beam operation, a wireless device may perform an uplink beamsweeping to access a cell.

In an example, a wireless device may be configured to monitor PDCCH onone or more beam pair links simultaneously depending on a capability ofa wireless device. This may increase robustness against beam pair linkblocking. A base station may transmit one or more messages to configurea wireless device to monitor PDCCH on one or more beam pair links indifferent PDCCH OFDM symbols. For example, a base station may transmithigher layer signaling (e.g. RRC signaling) or MAC CE comprisingparameters related to the Rx beam setting of a wireless device formonitoring PDCCH on one or more beam pair links. A base station maytransmit indication of spatial QCL assumption between an DL RS antennaport(s) (for example, cell-specific CSI-RS, or wireless device-specificCSI-RS, or SS block, or PBCH with or without DM-RSs of PBCH), and DL RSantenna port(s) for demodulation of DL control channel Signaling forbeam indication for a PDCCH may be MAC CE signaling, or RRC signaling,or DCI signaling, or specification-transparent and/or implicit method,and combination of these signaling methods.

For reception of unicast DL data channel, a base station may indicatespatial QCL parameters between DL RS antenna port(s) and DM-RS antennaport(s) of DL data channel. The base station may transmit DCI (e.g.downlink grants) comprising information indicating the RS antennaport(s). The information may indicate RS antenna port(s) which may beQCLed with the DM-RS antenna port(s). Different set of DM-RS antennaport(s) for a DL data channel may be indicated as QCL with different setof the RS antenna port(s).

FIG. 9A is an example of beam sweeping in a DL channel. In anRRC_INACTIVE state or RRC_IDLE state, a wireless device may assume thatSS blocks form an SS burst 940, and an SS burst set 950. The SS burstset 950 may have a given periodicity. For example, in a multi-beamoperation, a base station 120 may transmit SS blocks in multiple beams,together forming a SS burst 940. One or more SS blocks may betransmitted on one beam. If multiple SS bursts 940 are transmitted withmultiple beams, SS bursts together may form SS burst set 950.

A wireless device may further use CSI-RS in the multi-beam operation forestimating a beam quality of a links between a wireless device and abase station. A beam may be associated with a CSI-RS. For example, awireless device may, based on a RSRP measurement on CSI-RS, report abeam index, as indicated in a CRI for downlink beam selection, andassociated with a RSRP value of a beam. A CSI-RS may be transmitted on aCSI-RS resource including at least one of one or more antenna ports, oneor more time or frequency radio resources. A CSI-RS resource may beconfigured in a cell-specific way by common RRC signaling, or in awireless device-specific way by dedicated RRC signaling, and/or L1/L2signaling. Multiple wireless devices covered by a cell may measure acell-specific CSI-RS resource. A dedicated subset of wireless devicescovered by a cell may measure a wireless device-specific CSI-RSresource.

A CSI-RS resource may be transmitted periodically, or using aperiodictransmission, or using a multi-shot or semi-persistent transmission. Forexample, in a periodic transmission in FIG. 9A, a base station 120 maytransmit configured CSI-RS resources 940 periodically using a configuredperiodicity in a time domain. In an aperiodic transmission, a configuredCSI-RS resource may be transmitted in a dedicated time slot. In amulti-shot or semi-persistent transmission, a configured CSI-RS resourcemay be transmitted within a configured period. Beams used for CSI-RStransmission may have different beam width than beams used for SS-blockstransmission.

FIG. 9B is an example of a beam management procedure in an example newradio network. A base station 120 and/or a wireless device 110 mayperform a downlink L1/L2 beam management procedure. One or more of thefollowing downlink L1/L2 beam management procedures may be performedwithin one or more wireless devices 110 and one or more base stations120. In an example, a P-1 procedure 910 may be used to enable thewireless device 110 to measure one or more Transmission (Tx) beamsassociated with the base station 120 to support a selection of a firstset of Tx beams associated with the base station 120 and a first set ofRx beam(s) associated with a wireless device 110. For beamforming at abase station 120, a base station 120 may sweep a set of different TXbeams. For beamforming at a wireless device 110, a wireless device 110may sweep a set of different Rx beams. In an example, a P-2 procedure920 may be used to enable a wireless device 110 to measure one or moreTx beams associated with a base station 120 to possibly change a firstset of Tx beams associated with a base station 120. A P-2 procedure 920may be performed on a possibly smaller set of beams for beam refinementthan in the P-1 procedure 910. A P-2 procedure 920 may be a special caseof a P-1 procedure 910. In an example, a P-3 procedure 930 may be usedto enable a wireless device 110 to measure at least one Tx beamassociated with a base station 120 to change a first set of Rx beamsassociated with a wireless device 110.

A wireless device 110 may transmit one or more beam management reportsto a base station 120. In one or more beam management reports, awireless device 110 may indicate some beam pair quality parameters,comprising at least, one or more beam identifications; RSRP; PrecodingMatrix Indicator (PMI)/Channel Quality Indicator (CQI)/Rank Indicator(RI) of a subset of configured beams. Based on one or more beammanagement reports, a base station 120 may transmit to a wireless device110 a signal indicating that one or more beam pair links are one or moreserving beams. A base station 120 may transmit PDCCH and PDSCH for awireless device 110 using one or more serving beams.

In an example embodiment, new radio network may support a BandwidthAdaptation (BA). In an example, receive and/or transmit bandwidthsconfigured by an UE employing a BA may not be large. For example, areceive and/or transmit bandwidths may not be as large as a bandwidth ofa cell. Receive and/or transmit bandwidths may be adjustable. Forexample, a UE may change receive and/or transmit bandwidths, e.g., toshrink during period of low activity to save power. For example, a UEmay change a location of receive and/or transmit bandwidths in afrequency domain, e.g. to increase scheduling flexibility. For example,a UE may change a subcarrier spacing, e.g. to allow different services.

In an example embodiment, a subset of a total cell bandwidth of a cellmay be referred to as a Bandwidth Part (BWP). A base station mayconfigure a UE with one or more BWPs to achieve a BA. For example, abase station may indicate, to a UE, which of the one or more(configured) BWPs is an active BWP.

FIG. 10 is an example diagram of 3 BWPs configured: BWP1 (1010 and 1050)with a width of 40 MHz and subcarrier spacing of 15 kHz; BWP2 (1020 and1040) with a width of 10 MHz and subcarrier spacing of 15 kHz; BWP3 1030with a width of 20 MHz and subcarrier spacing of 60 kHz.

In an example, a UE, configured for operation in one or more BWPs of acell, may be configured by one or more higher layers (e.g. RRC layer)for a cell a set of one or more BWPs (e.g., at most four BWPs) forreceptions by the UE (DL BWP set) in a DL bandwidth by at least oneparameter DL-BWP and a set of one or more BWPs (e.g., at most four BWPs)for transmissions by a UE (UL BWP set) in an UL bandwidth by at leastone parameter UL-BWP for a cell.

To enable BA on the PCell, a base station may configure a UE with one ormore UL and DL BWP pairs. To enable BA on SCells (e.g., in case of CA),a base station may configure a UE at least with one or more DL BWPs(e.g., there may be none in an UL).

In an example, an initial active DL BWP may be defined by at least oneof a location and number of contiguous PRBs, a subcarrier spacing, or acyclic prefix, for a control resource set for at least one common searchspace. For operation on the PCell, one or more higher layer parametersmay indicate at least one initial UL BWP for a random access procedure.If a UE is configured with a secondary carrier on a primary cell, the UEmay be configured with an initial BWP for random access procedure on asecondary carrier.

In an example, for unpaired spectrum operation, a UE may expect that acenter frequency for a DL BWP may be same as a center frequency for a ULBWP.

For example, for a DL BWP or an UL BWP in a set of one or more DL BWPsor one or more UL BWPs, respectively, a base station maysemi-statistically configure a UE for a cell with one or more parametersindicating at least one of following: a subcarrier spacing; a cyclicprefix; a number of contiguous PRBs; an index in the set of one or moreDL BWPs and/or one or more UL BWPs; a link between a DL BWP and an ULBWP from a set of configured DL BWPs and UL BWPs; a DCI detection to aPDSCH reception timing; a PDSCH reception to a HARQ-ACK transmissiontiming value; a DCI detection to a PUSCH transmission timing value; anoffset of a first PRB of a DL bandwidth or an UL bandwidth,respectively, relative to a first PRB of a bandwidth.

In an example, for a DL BWP in a set of one or more DL BWPs on a PCell,a base station may configure a UE with one or more control resource setsfor at least one type of common search space and/or one UE-specificsearch space. For example, a base station may not configure a UE withouta common search space on a PCell, or on a PSCell, in an active DL BWP.

For an UL BWP in a set of one or more UL BWPs, a base station mayconfigure a UE with one or more resource sets for one or more PUCCHtransmissions.

In an example, if a DCI comprises a BWP indicator field, a BWP indicatorfield value may indicate an active DL BWP, from a configured DL BWP set,for one or more DL receptions. If a DCI comprises a BWP indicator field,a BWP indicator field value may indicate an active UL BWP, from aconfigured UL BWP set, for one or more UL transmissions.

In an example, for a PCell, a base station may semi-statisticallyconfigure a UE with a default DL BWP among configured DL BWPs. If a UEis not provided a default DL BWP, a default BWP may be an initial activeDL BWP.

In an example, a base station may configure a UE with a timer value fora PCell. For example, a UE may start a timer, referred to as BWPinactivity timer, when a UE detects a DCI indicating an active DL BWP,other than a default DL BWP, for a paired spectrum operation or when aUE detects a DCI indicating an active DL BWP or UL BWP, other than adefault DL BWP or UL BWP, for an unpaired spectrum operation. The UE mayincrement the timer by an interval of a first value (e.g., the firstvalue may be 1 millisecond or 0.5 milliseconds) if the UE does notdetect a DCI during the interval for a paired spectrum operation or foran unpaired spectrum operation. In an example, the timer may expire whenthe timer is equal to the timer value. A UE may switch to the default DLBWP from an active DL BWP when the timer expires.

In an example, a base station may semi-statistically configure a UE withone or more BWPs. A UE may switch an active BWP from a first BWP to asecond BWP in response to receiving a DCI indicating the second BWP asan active BWP and/or in response to an expiry of BWP inactivity timer(for example, the second BWP may be a default BWP). For example, FIG. 10is an example diagram of 3 BWPs configured, BWP1 (1010 and 1050), BWP2(1020 and 1040), and BWP3 (1030). BWP2 (1020 and 1040) may be a defaultBWP. BWP1 (1010) may be an initial active BWP. In an example, a UE mayswitch an active BWP from BWP1 1010 to BWP2 1020 in response to anexpiry of BWP inactivity timer. For example, a UE may switch an activeBWP from BWP2 1020 to BWP3 1030 in response to receiving a DCIindicating BWP3 1030 as an active BWP. Switching an active BWP from BWP31030 to BWP2 1040 and/or from BWP2 1040 to BWP1 1050 may be in responseto receiving a DCI indicating an active BWP and/or in response to anexpiry of BWP inactivity timer.

In an example, if a UE is configured for a secondary cell with a defaultDL BWP among configured DL BWPs and a timer value, UE procedures on asecondary cell may be same as on a primary cell using the timer valuefor the secondary cell and the default DL BWP for the secondary cell.

In an example, if a base station configures a UE with a first active DLBWP and a first active UL BWP on a secondary cell or carrier, a UE mayemploy an indicated DL BWP and an indicated UL BWP on a secondary cellas a respective first active DL BWP and first active UL BWP on asecondary cell or carrier.

FIG. 11A and FIG. 11B show packet flows employing a multi connectivity(e.g. dual connectivity, multi connectivity, tight interworking, and/orthe like). FIG. 11A is an example diagram of a protocol structure of awireless device 110 (e.g. UE) with CA and/or multi connectivity as peran aspect of an embodiment. FIG. 11B is an example diagram of a protocolstructure of multiple base stations with CA and/or multi connectivity asper an aspect of an embodiment. The multiple base stations may comprisea master node, MN 1130 (e.g. a master node, a master base station, amaster gNB, a master eNB, and/or the like) and a secondary node, SN 1150(e.g. a secondary node, a secondary base station, a secondary gNB, asecondary eNB, and/or the like). A master node 1130 and a secondary node1150 may co-work to communicate with a wireless device 110.

When multi connectivity is configured for a wireless device 110, thewireless device 110, which may support multiple reception/transmissionfunctions in an RRC connected state, may be configured to utilize radioresources provided by multiple schedulers of a multiple base stations.Multiple base stations may be inter-connected via a non-ideal or idealbackhaul (e.g. Xn interface, X2 interface, and/or the like). A basestation involved in multi connectivity for a certain wireless device mayperform at least one of two different roles: a base station may eitheract as a master base station or as a secondary base station. In multiconnectivity, a wireless device may be connected to one master basestation and one or more secondary base stations. In an example, a masterbase station (e.g. the MN 1130) may provide a master cell group (MCG)comprising a primary cell and/or one or more secondary cells for awireless device (e.g. the wireless device 110). A secondary base station(e.g. the SN 1150) may provide a secondary cell group (SCG) comprising aprimary secondary cell (PSCell) and/or one or more secondary cells for awireless device (e.g. the wireless device 110).

In multi connectivity, a radio protocol architecture that a beareremploys may depend on how a bearer is setup. In an example, threedifferent type of bearer setup options may be supported: an MCG bearer,an SCG bearer, and/or a split bearer. A wireless device mayreceive/transmit packets of an MCG bearer via one or more cells of theMCG, and/or may receive/transmits packets of an SCG bearer via one ormore cells of an SCG. Multi-connectivity may also be described as havingat least one bearer configured to use radio resources provided by thesecondary base station. Multi-connectivity may or may not beconfigured/implemented in some of the example embodiments.

In an example, a wireless device (e.g. Wireless Device 110) may transmitand/or receive: packets of an MCG bearer via an SDAP layer (e.g. SDAP1110), a PDCP layer (e.g. NR PDCP 1111), an RLC layer (e.g. MN RLC1114), and a MAC layer (e.g. MN MAC 1118); packets of a split bearer viaan SDAP layer (e.g. SDAP 1110), a PDCP layer (e.g. NR PDCP 1112), one ofa master or secondary RLC layer (e.g. MN RLC 1115, SN RLC 1116), and oneof a master or secondary MAC layer (e.g. MN MAC 1118, SN MAC 1119);and/or packets of an SCG bearer via an SDAP layer (e.g. SDAP 1110), aPDCP layer (e.g. NR PDCP 1113), an RLC layer (e.g. SN RLC 1117), and aMAC layer (e.g. MN MAC 1119).

In an example, a master base station (e.g. MN 1130) and/or a secondarybase station (e.g. SN 1150) may transmit/receive: packets of an MCGbearer via a master or secondary node SDAP layer (e.g. SDAP 1120, SDAP1140), a master or secondary node PDCP layer (e.g. NR PDCP 1121, NR PDCP1142), a master node RLC layer (e.g. MN RLC 1124, MN RLC 1125), and amaster node MAC layer (e.g. MN MAC 1128); packets of an SCG bearer via amaster or secondary node SDAP layer (e.g. SDAP 1120, SDAP 1140), amaster or secondary node PDCP layer (e.g. NR PDCP 1122, NR PDCP 1143), asecondary node RLC layer (e.g. SN RLC 1146, SN RLC 1147), and asecondary node MAC layer (e.g. SN MAC 1148); packets of a split bearervia a master or secondary node SDAP layer (e.g. SDAP 1120, SDAP 1140), amaster or secondary node PDCP layer (e.g. NR PDCP 1123, NR PDCP 1141), amaster or secondary node RLC layer (e.g. MN RLC 1126, SN RLC 1144, SNRLC 1145, MN RLC 1127), and a master or secondary node MAC layer (e.g.MN MAC 1128, SN MAC 1148).

In multi connectivity, a wireless device may configure multiple MACentities: one MAC entity (e.g. MN MAC 1118) for a master base station,and other MAC entities (e.g. SN MAC 1119) for a secondary base station.In multi-connectivity, a configured set of serving cells for a wirelessdevice may comprise two subsets: an MCG comprising serving cells of amaster base station, and SCGs comprising serving cells of a secondarybase station. For an SCG, one or more of following configurations may beapplied: at least one cell of an SCG has a configured UL CC and at leastone cell of a SCG, named as primary secondary cell (PSCell, PCell ofSCG, or sometimes called PCell), is configured with PUCCH resources;when an SCG is configured, there may be at least one SCG bearer or oneSplit bearer; upon detection of a physical layer problem or a randomaccess problem on a PSCell, or a number of NR RLC retransmissions hasbeen reached associated with the SCG, or upon detection of an accessproblem on a PSCell during a SCG addition or a SCG change: an RRCconnection re-establishment procedure may not be triggered, ULtransmissions towards cells of an SCG may be stopped, a master basestation may be informed by a wireless device of a SCG failure type, forsplit bearer, a DL data transfer over a master base station may bemaintained; an NR RLC acknowledged mode (AM) bearer may be configuredfor a split bearer; PCell and/or PSCell may not be de-activated; PSCellmay be changed with a SCG change procedure (e.g. with security keychange and a RACH procedure); and/or a bearer type change between asplit bearer and a SCG bearer or simultaneous configuration of a SCG anda split bearer may or may not supported.

With respect to interaction between a master base station and asecondary base stations for multi-connectivity, one or more of thefollowing may be applied: a master base station and/or a secondary basestation may maintain RRM measurement configurations of a wirelessdevice; a master base station may (e.g. based on received measurementreports, traffic conditions, and/or bearer types) may decide to requesta secondary base station to provide additional resources (e.g. servingcells) for a wireless device; upon receiving a request from a masterbase station, a secondary base station may create/modify a containerthat may result in configuration of additional serving cells for awireless device (or decide that the secondary base station has noresource available to do so); for a UE capability coordination, a masterbase station may provide (a part of) an AS configuration and UEcapabilities to a secondary base station; a master base station and asecondary base station may exchange information about a UE configurationby employing of RRC containers (inter-node messages) carried via Xnmessages; a secondary base station may initiate a reconfiguration of thesecondary base station existing serving cells (e.g. PUCCH towards thesecondary base station); a secondary base station may decide which cellis a PSCell within a SCG; a master base station may or may not changecontent of RRC configurations provided by a secondary base station; incase of a SCG addition and/or a SCG SCell addition, a master basestation may provide recent (or the latest) measurement results for SCGcell(s); a master base station and secondary base stations may receiveinformation of SFN and/or subframe offset of each other from OAM and/orvia an Xn interface, (e.g. for a purpose of DRX alignment and/oridentification of a measurement gap). In an example, when adding a newSCG SCell, dedicated RRC signaling may be used for sending requiredsystem information of a cell as for CA, except for a SFN acquired from aMIB of a PSCell of a SCG.

FIG. 12 is an example diagram of a random access procedure. One or moreevents may trigger a random access procedure. For example, one or moreevents may be at least one of following: initial access from RRC_IDLE,RRC connection re-establishment procedure, handover, DL or UL dataarrival during RRC_CONNECTED when UL synchronization status isnon-synchronized, transition from RRC_Inactive, and/or request for othersystem information. For example, a PDCCH order, a MAC entity, and/or abeam failure indication may initiate a random access procedure.

In an example embodiment, a random access procedure may be at least oneof a contention based random access procedure and a contention freerandom access procedure. For example, a contention based random accessprocedure may comprise, one or more Msg 1 1220 transmissions, one ormore Msg2 1230 transmissions, one or more Msg3 1240 transmissions, andcontention resolution 1250. For example, a contention free random accessprocedure may comprise one or more Msg 1 1220 transmissions and one ormore Msg2 1230 transmissions.

In an example, a base station may transmit (e.g., unicast, multicast, orbroadcast), to a UE, a RACH configuration 1210 via one or more beams.The RACH configuration 1210 may comprise one or more parametersindicating at least one of following: available set of PRACH resourcesfor a transmission of a random access preamble, initial preamble power(e.g., random access preamble initial received target power), an RSRPthreshold for a selection of a SS block and corresponding PRACHresource, a power-ramping factor (e.g., random access preamble powerramping step), random access preamble index, a maximum number ofpreamble transmission, preamble group A and group B, a threshold (e.g.,message size) to determine the groups of random access preambles, a setof one or more random access preambles for system information requestand corresponding PRACH resource(s), if any, a set of one or more randomaccess preambles for beam failure recovery request and correspondingPRACH resource(s), if any, a time window to monitor RA response(s), atime window to monitor response(s) on beam failure recovery request,and/or a contention resolution timer.

In an example, the Msg1 1220 may be one or more transmissions of arandom access preamble. For a contention based random access procedure,a UE may select a SS block with a RSRP above the RSRP threshold. Ifrandom access preambles group B exists, a UE may select one or morerandom access preambles from a group A or a group B depending on apotential Msg3 1240 size. If a random access preambles group B does notexist, a UE may select the one or more random access preambles from agroup A. A UE may select a random access preamble index randomly (e.g.with equal probability or a normal distribution) from one or more randomaccess preambles associated with a selected group. If a base stationsemi-statistically configures a UE with an association between randomaccess preambles and SS blocks, the UE may select a random accesspreamble index randomly with equal probability from one or more randomaccess preambles associated with a selected SS block and a selectedgroup.

For example, a UE may initiate a contention free random access procedurebased on a beam failure indication from a lower layer. For example, abase station may semi-statistically configure a UE with one or morecontention free PRACH resources for beam failure recovery requestassociated with at least one of SS blocks and/or CSI-RSs. If at leastone of SS blocks with a RSRP above a first RSRP threshold amongstassociated SS blocks or at least one of CSI-RSs with a RSRP above asecond RSRP threshold amongst associated CSI-RSs is available, a UE mayselect a random access preamble index corresponding to a selected SSblock or CSI-RS from a set of one or more random access preambles forbeam failure recovery request.

For example, a UE may receive, from a base station, a random accesspreamble index via PDCCH or RRC for a contention free random accessprocedure. If a base station does not configure a UE with at least onecontention free PRACH resource associated with SS blocks or CSI-RS, theUE may select a random access preamble index. If a base stationconfigures a UE with one or more contention free PRACH resourcesassociated with SS blocks and at least one SS block with a RSRP above afirst RSRP threshold amongst associated SS blocks is available, the UEmay select the at least one SS block and select a random access preamblecorresponding to the at least one SS block. If a base station configuresa UE with one or more contention free PRACH resources associated withCSI-RSs and at least one CSI-RS with a RSRP above a second RSPRthreshold amongst the associated CSI-RSs is available, the UE may selectthe at least one CSI-RS and select a random access preamblecorresponding to the at least one CSI-RS.

A UE may perform one or more Msg1 1220 transmissions by transmitting theselected random access preamble. For example, if a UE selects an SSblock and is configured with an association between one or more PRACHoccasions and one or more SS blocks, the UE may determine an PRACHoccasion from one or more PRACH occasions corresponding to a selected SSblock. For example, if a UE selects a CSI-RS and is configured with anassociation between one or more PRACH occasions and one or more CSI-RSs,the UE may determine a PRACH occasion from one or more PRACH occasionscorresponding to a selected CSI-RS. A UE may transmit, to a basestation, a selected random access preamble via a selected PRACHoccasions. A UE may determine a transmit power for a transmission of aselected random access preamble at least based on an initial preamblepower and a power-ramping factor. A UE may determine a RA-RNTIassociated with a selected PRACH occasions in which a selected randomaccess preamble is transmitted. For example, a UE may not determine aRA-RNTI for a beam failure recovery request. A UE may determine anRA-RNTI at least based on an index of a first OFDM symbol and an indexof a first slot of a selected PRACH occasions, and/or an uplink carrierindex for a transmission of Msg1 1220.

In an example, a UE may receive, from a base station, a random accessresponse, Msg 2 1230. A UE may start a time window (e.g., ra-ResponseWindow) to monitor a random access response. For beam failure recoveryrequest, a base station may configure a UE with a different time window(e.g., bfr-ResponseWindow) to monitor response on beam failure recoveryrequest. For example, a UE may start a time window (e.g.,ra-ResponseWindow or bfr-Response Window) at a start of a first PDCCHoccasion after a fixed duration of one or more symbols from an end of apreamble transmission. If a UE transmits multiple preambles, the UE maystart a time window at a start of a first PDCCH occasion after a fixedduration of one or more symbols from an end of a first preambletransmission. A UE may monitor a PDCCH of a cell for at least one randomaccess response identified by a RA-RNTI or for at least one response tobeam failure recovery request identified by a C-RNTI while a timer for atime window is running.

In an example, a UE may consider a reception of random access responsesuccessful if at least one random access response comprises a randomaccess preamble identifier corresponding to a random access preambletransmitted by the UE. A UE may consider the contention free randomaccess procedure successfully completed if a reception of random accessresponse is successful. If a contention free random access procedure istriggered for a beam failure recovery request, a UE may consider acontention free random access procedure successfully complete if a PDCCHtransmission is addressed to a C-RNTI. In an example, if at least onerandom access response comprises a random access preamble identifier, aUE may consider the random access procedure successfully completed andmay indicate a reception of an acknowledgement for a system informationrequest to upper layers. If a UE has signaled multiple preambletransmissions, the UE may stop transmitting remaining preambles (if any)in response to a successful reception of a corresponding random accessresponse.

In an example, a UE may perform one or more Msg 3 1240 transmissions inresponse to a successful reception of random access response (e.g., fora contention based random access procedure). A UE may adjust an uplinktransmission timing based on a timing advanced command indicated by arandom access response and may transmit one or more transport blocksbased on an uplink grant indicated by a random access response.Subcarrier spacing for PUSCH transmission for Msg3 1240 may be providedby at least one higher layer (e.g. RRC) parameter. A UE may transmit arandom access preamble via PRACH and Msg3 1240 via PUSCH on a same cell.A base station may indicate an UL BWP for a PUSCH transmission of Msg31240 via system information block. A UE may employ HARQ for aretransmission of Msg 3 1240.

In an example, multiple UEs may perform Msg 1 1220 by transmitting asame preamble to a base station and receive, from the base station, asame random access response comprising an identity (e.g., TC-RNTI).Contention resolution 1250 may ensure that a UE does not incorrectly usean identity of another UE. For example, contention resolution 1250 maybe based on C-RNTI on PDCCH or a UE contention resolution identity onDL-SCH. For example, if a base station assigns a C-RNTI to a UE, the UEmay perform contention resolution 1250 based on a reception of a PDCCHtransmission that is addressed to the C-RNTI. In response to detectionof a C-RNTI on a PDCCH, a UE may consider contention resolution 1250successful and may consider a random access procedure successfullycompleted. If a UE has no valid C-RNTI, a contention resolution may beaddressed by employing a TC-RNTI. For example, if a MAC PDU issuccessfully decoded and a MAC PDU comprises a UE contention resolutionidentity MAC CE that matches the CCCH SDU transmitted in Msg3 1250, a UEmay consider the contention resolution 1250 successful and may considerthe random access procedure successfully completed.

FIG. 13 is an example structure for MAC entities as per an aspect of anembodiment. In an example, a wireless device may be configured tooperate in a multi-connectivity mode. A wireless device in RRC_CONNECTEDwith multiple RX/TX may be configured to utilize radio resourcesprovided by multiple schedulers located in a plurality of base stations.The plurality of base stations may be connected via a non-ideal or idealbackhaul over the Xn interface. In an example, a base station in aplurality of base stations may act as a master base station or as asecondary base station. A wireless device may be connected to one masterbase station and one or more secondary base stations. A wireless devicemay be configured with multiple MAC entities, e.g. one MAC entity formaster base station, and one or more other MAC entities for secondarybase station(s). In an example, a configured set of serving cells for awireless device may comprise two subsets: an MCG comprising servingcells of a master base station, and one or more SCGs comprising servingcells of a secondary base station(s). FIG. 13 illustrates an examplestructure for MAC entities when MCG and SCG are configured for awireless device.

In an example, at least one cell in a SCG may have a configured UL CC,wherein a cell of at least one cell may be called PSCell or PCell ofSCG, or sometimes may be simply called PCell. A PSCell may be configuredwith PUCCH resources. In an example, when a SCG is configured, there maybe at least one SCG bearer or one split bearer. In an example, upondetection of a physical layer problem or a random access problem on aPSCell, or upon reaching a number of RLC retransmissions associated withthe SCG, or upon detection of an access problem on a PSCell during a SCGaddition or a SCG change: an RRC connection re-establishment proceduremay not be triggered, UL transmissions towards cells of an SCG may bestopped, a master base station may be informed by a UE of a SCG failuretype and DL data transfer over a master base station may be maintained.

In an example, a MAC sublayer may provide services such as data transferand radio resource allocation to upper layers (e.g. 1310 or 1320). A MACsublayer may comprise a plurality of MAC entities (e.g. 1350 and 1360).A MAC sublayer may provide data transfer services on logical channels.To accommodate different kinds of data transfer services, multiple typesof logical channels may be defined. A logical channel may supporttransfer of a particular type of information. A logical channel type maybe defined by what type of information (e.g., control or data) istransferred. For example, BCCH, PCCH, CCCH and DCCH may be controlchannels and DTCH may be a traffic channel. In an example, a first MACentity (e.g. 1310) may provide services on PCCH, BCCH, CCCH, DCCH, DTCHand MAC control elements. In an example, a second MAC entity (e.g. 1320)may provide services on BCCH, DCCH, DTCH and MAC control elements.

A MAC sublayer may expect from a physical layer (e.g. 1330 or 1340)services such as data transfer services, signaling of HARQ feedback,signaling of scheduling request or measurements (e.g. CQI). In anexample, in dual connectivity, two MAC entities may be configured for awireless device: one for MCG and one for SCG. A MAC entity of wirelessdevice may handle a plurality of transport channels. In an example, afirst MAC entity may handle first transport channels comprising a PCCHof MCG, a first BCH of MCG, one or more first DL-SCHs of MCG, one ormore first UL-SCHs of MCG and one or more first RACHs of MCG. In anexample, a second MAC entity may handle second transport channelscomprising a second BCH of SCG, one or more second DL-SCHs of SCG, oneor more second UL-SCHs of SCG and one or more second RACHs of SCG.

In an example, if a MAC entity is configured with one or more SCells,there may be multiple DL-SCHs and there may be multiple UL-SCHs as wellas multiple RACHs per MAC entity. In an example, there may be one DL-SCHand UL-SCH on a SpCell. In an example, there may be one DL-SCH, zero orone UL-SCH and zero or one RACH for an SCell. A DL-SCH may supportreceptions using different numerologies and/or TTI duration within a MACentity. A UL-SCH may also support transmissions using differentnumerologies and/or TTI duration within the MAC entity.

In an example, a MAC sublayer may support different functions and maycontrol these functions with a control (e.g. 1355 or 1365) element.Functions performed by a MAC entity may comprise mapping between logicalchannels and transport channels (e.g., in uplink or downlink),multiplexing (e.g. 1352 or 1362) of MAC SDUs from one or differentlogical channels onto transport blocks (TB) to be delivered to thephysical layer on transport channels (e.g., in uplink), demultiplexing(e.g. 1352 or 1362) of MAC SDUs to one or different logical channelsfrom transport blocks (TB) delivered from the physical layer ontransport channels (e.g., in downlink), scheduling information reporting(e.g., in uplink), error correction through HARQ in uplink or downlink(e.g. 1363), and logical channel prioritization in uplink (e.g. 1351 or1361). A MAC entity may handle a random access process (e.g. 1354 or1364).

FIG. 14 is an example diagram of a RAN architecture comprising one ormore base stations. In an example, a protocol stack (e.g. RRC, SDAP,PDCP, RLC, MAC, and PHY) may be supported at a node. A base station(e.g. gNB 120A or 120B) may comprise a base station central unit (CU)(e.g. gNB-CU 1420A or 1420B) and at least one base station distributedunit (DU) (e.g. gNB-DU 1430A, 1430B, 1430C, or 1430D) if a functionalsplit is configured. Upper protocol layers of a base station may belocated in a base station CU, and lower layers of the base station maybe located in the base station DUs. An Fl interface (e.g. CU-DUinterface) connecting a base station CU and base station DUs may be anideal or non-ideal backhaul. Fl-C may provide a control plane connectionover an Fl interface, and Fl-U may provide a user plane connection overthe Fl interface. In an example, an Xn interface may be configuredbetween base station CUs.

In an example, a base station CU may comprise an RRC function, an SDAPlayer, and a PDCP layer, and base station DUs may comprise an RLC layer,a MAC layer, and a PHY layer. In an example, various functional splitoptions between a base station CU and base station DUs may be possibleby locating different combinations of upper protocol layers (RANfunctions) in a base station CU and different combinations of lowerprotocol layers (RAN functions) in base station DUs. A functional splitmay support flexibility to move protocol layers between a base stationCU and base station DUs depending on service requirements and/or networkenvironments.

In an example, functional split options may be configured per basestation, per base station CU, per base station DU, per UE, per bearer,per slice, or with other granularities. In per base station CU split, abase station CU may have a fixed split option, and base station DUs maybe configured to match a split option of a base station CU. In per basestation DU split, a base station DU may be configured with a differentsplit option, and a base station CU may provide different split optionsfor different base station DUs. In per UE split, a base station (basestation CU and at least one base station DUs) may provide differentsplit options for different wireless devices. In per bearer split,different split options may be utilized for different bearers. In perslice splice, different split options may be applied for differentslices.

FIG. 15 is an example diagram showing RRC state transitions of awireless device. In an example, a wireless device may be in at least oneRRC state among an RRC connected state (e.g. RRC Connected 1530,RRC_Connected), an RRC idle state (e.g. RRC Idle 1510, RRC_Idle), and/oran RRC inactive state (e.g. RRC Inactive 1520, RRC_Inactive). In anexample, in an RRC connected state, a wireless device may have at leastone RRC connection with at least one base station (e.g. gNB and/or eNB),which may have a UE context of the wireless device. A UE context (e.g. awireless device context) may comprise at least one of an access stratumcontext, one or more radio link configuration parameters, bearer (e.g.data radio bearer (DRB), signaling radio bearer (SRB), logical channel,QoS flow, PDU session, and/or the like) configuration information,security information, PHY/MAC/RLC/PDCP/SDAP layer configurationinformation, and/or the like configuration information for a wirelessdevice. In an example, in an RRC idle state, a wireless device may nothave an RRC connection with a base station, and a UE context of awireless device may not be stored in a base station. In an example, inan RRC inactive state, a wireless device may not have an RRC connectionwith a base station. A UE context of a wireless device may be stored ina base station, which may be called as an anchor base station (e.g. lastserving base station).

In an example, a wireless device may transition a UE RRC state betweenan RRC idle state and an RRC connected state in both ways (e.g.connection release 1540 or connection establishment 1550; or connectionreestablishment) and/or between an RRC inactive state and an RRCconnected state in both ways (e.g. connection inactivation 1570 orconnection resume 1580). In an example, a wireless device may transitionits RRC state from an RRC inactive state to an RRC idle state (e.g.connection release 1560).

In an example, an anchor base station may be a base station that maykeep a UE context (a wireless device context) of a wireless device atleast during a time period that a wireless device stays in a RANnotification area (RNA) of an anchor base station, and/or that awireless device stays in an RRC inactive state. In an example, an anchorbase station may be a base station that a wireless device in an RRCinactive state was lastly connected to in a latest RRC connected stateor that a wireless device lastly performed an RNA update procedure in.In an example, an RNA may comprise one or more cells operated by one ormore base stations. In an example, a base station may belong to one ormore RNAs. In an example, a cell may belong to one or more RNAs.

In an example, a wireless device may transition a UE RRC state from anRRC connected state to an RRC inactive state in a base station. Awireless device may receive RNA information from the base station. RNAinformation may comprise at least one of an RNA identifier, one or morecell identifiers of one or more cells of an RNA, a base stationidentifier, an IP address of the base station, an AS context identifierof the wireless device, a resume identifier, and/or the like.

In an example, an anchor base station may broadcast a message (e.g. RANpaging message) to base stations of an RNA to reach to a wireless devicein an RRC inactive state, and/or the base stations receiving the messagefrom the anchor base station may broadcast and/or multicast anothermessage (e.g. paging message) to wireless devices in their coveragearea, cell coverage area, and/or beam coverage area associated with theRNA through an air interface.

In an example, when a wireless device in an RRC inactive state movesinto a new RNA, the wireless device may perform an RNA update (RNAU)procedure, which may comprise a random access procedure by the wirelessdevice and/or a UE context retrieve procedure. A UE context retrieve maycomprise: receiving, by a base station from a wireless device, a randomaccess preamble; and fetching, by a base station, a UE context of thewireless device from an old anchor base station. Fetching may comprise:sending a retrieve UE context request message comprising a resumeidentifier to the old anchor base station and receiving a retrieve UEcontext response message comprising the UE context of the wirelessdevice from the old anchor base station.

In an example embodiment, a wireless device in an RRC inactive state mayselect a cell to camp on based on at least a on measurement results forone or more cells, a cell where a wireless device may monitor an RNApaging message and/or a core network paging message from a base station.In an example, a wireless device in an RRC inactive state may select acell to perform a random access procedure to resume an RRC connectionand/or to transmit one or more packets to a base station (e.g. to anetwork). In an example, if a cell selected belongs to a different RNAfrom an RNA for a wireless device in an RRC inactive state, the wirelessdevice may initiate a random access procedure to perform an RNA updateprocedure. In an example, if a wireless device in an RRC inactive statehas one or more packets, in a buffer, to transmit to a network, thewireless device may initiate a random access procedure to transmit oneor more packets to a base station of a cell that the wireless deviceselects. A random access procedure may be performed with two messages(e.g. 2 stage random access) and/or four messages (e.g. 4 stage randomaccess) between the wireless device and the base station.

In an example embodiment, a base station receiving one or more uplinkpackets from a wireless device in an RRC inactive state may fetch a UEcontext of a wireless device by transmitting a retrieve UE contextrequest message for the wireless device to an anchor base station of thewireless device based on at least one of an AS context identifier, anRNA identifier, a base station identifier, a resume identifier, and/or acell identifier received from the wireless device. In response tofetching a UE context, a base station may transmit a path switch requestfor a wireless device to a core network entity (e.g. AMF, MME, and/orthe like). A core network entity may update a downlink tunnel endpointidentifier for one or more bearers established for the wireless devicebetween a user plane core network entity (e.g. UPF, S-GW, and/or thelike) and a RAN node (e.g. the base station), e.g. changing a downlinktunnel endpoint identifier from an address of the anchor base station toan address of the base station.

A gNB may communicate with a wireless device via a wireless networkemploying one or more new radio technologies. The one or more radiotechnologies may comprise at least one of: multiple technologies relatedto physical layer; multiple technologies related to medium accesscontrol layer; and/or multiple technologies related to radio resourcecontrol layer. Example embodiments of enhancing the one or more radiotechnologies may improve performance of a wireless network. Exampleembodiments may increase the system throughput, or data rate oftransmission. Example embodiments may reduce battery consumption of awireless device. Example embodiments may improve latency of datatransmission between a gNB and a wireless device. Example embodimentsmay improve network coverage of a wireless network. Example embodimentsmay improve transmission efficiency of a wireless network.

Example of Carrier Aggregation

In a carrier aggregation (CA), two or more component carriers (CCs) maybe aggregated. A wireless device may simultaneously receive or transmiton one or more CCs depending on capabilities of the wireless device. Inan example, the CA may be supported for contiguous CCs. In an example,the CA may be supported for non-contiguous CCs.

When configured with CA, a base station and/or a wireless device mayemploy an activation/deactivation mechanism of an SCell for an efficientbattery consumption. When a wireless device is configured with one ormore SCells, a gNB may activate or deactivate at least one of the one ormore SCells. Upon configuration of an SCell, the SCell may bedeactivated.

In an example, a wireless device may activate/deactivate an SCell inresponse to receiving an SCell Activation/Deactivation MAC CE.

In an example, a base station may transmit, to a wireless device, one ormore messages comprising an sCellDeactivationTimer timer. In an example,a wireless device may deactivate an SCell in response to an expiry ofthe sCellDeactivationTimer timer.

When a wireless device receives an SCell Activation/Deactivation MAC CEactivating an SCell, the wireless device may activate the SCell. Inresponse to the activating the SCell, the wireless device may performoperations comprising SRS transmissions on the SCell, CQI/PMI/RI/CRIreporting for the SCell on a PCell, PDCCH monitoring on the SCell, PDCCHmonitoring for the SCell on the PCell, and/or PUCCH transmissions on theSCell.

In an example, in response to the activating the SCell, the wirelessdevice may start or restart an sCellDeactivationTimer timer associatedwith the SCell. The wireless device may start the sCellDeactivationTimertimer in the slot when the SCell Activation/Deactivation MAC CE has beenreceived. In an example, in response to the activating the SCell, thewireless device may (re-)initialize one or more suspended configureduplink grants of a configured grant Type 1 associated with the SCellaccording to a stored configuration. In an example, in response to theactivating the SCell, the wireless device may trigger PHR.

In an example, when a wireless device receives an SCellActivation/Deactivation MAC CE deactivating an activated SCell, thewireless device may deactivate the activated SCell.

In an example, when an sCellDeactivationTimer timer associated with anactivated SCell expires, the wireless device may deactivate theactivated SCell. In response to the deactivating the activated SCell,the wireless device may stop the sCellDeactivationTimer timer associatedwith the activated SCell. In response to the deactivating the activatedSCell, the wireless device may stop the BWP inactivity timer associatedwith the activated SCell. In response to the deactivating the activatedSCell, the wireless device may deactivate any active BWP associated withthe activated SCell.

In an example, when at least one first PDCCH on an activated SCellindicates an uplink grant or a downlink assignment, a wireless devicemay restart an sCellDeactivationTimer timer associated with theactivated SCell. In an example, when at least one second PDCCH on aserving cell (e.g. a PCell or an SCell configured with PUCCH, i.e. PUCCHSCell) scheduling the activated SCell indicates an uplink grant or adownlink assignment for the activated SCell, a wireless device mayrestart an sCellDeactivationTimer timer associated with the activatedSCell.

In an example, when an SCell is deactivated, if there is an ongoingrandom access procedure on the SCell, a wireless device may abort theongoing random access procedure on the SCell.

Example of SCell Activation/Deactivation MAC-CE

In an example of an SCell Activation/Deactivation MAC CE of one octet, afirst MAC PDU subheader with a first LCID may identify the SCellActivation/Deactivation MAC CE of one octet. The SCellActivation/Deactivation MAC CE of one octet may have a fixed size. In anexample of the first LCID, the SCell Activation/Deactivation MAC CE ofone octet may comprise a single octet. The single octet may comprise afirst number of C-fields (e.g. seven) and a second number of R-fields(e.g. one).

In an example of an SCell Activation/Deactivation MAC CE of four octets,a second MAC PDU subheader with a second LCID may identify the SCellActivation/Deactivation MAC CE of four octets. In an example of thesecond LCID, the SCell Activation/Deactivation MAC CE of four octets mayhave a fixed size. The SCell Activation/Deactivation MAC CE of fouroctets may comprise four octets. The four octets may comprise a thirdnumber of C-fields (e.g. 31) and a fourth number of R-fields (e.g. 1).

In an example, a C, field may indicate an activation/deactivation statusof an SCell with an SCell index i, if a SCell with SCell index i isconfigured. In an example, when the C, field is set to one, an SCellwith an SCell index i may be activated. In an example, when the C, fieldis set to zero, an SCell with an SCell index i may be deactivated. In anexample, if there is no SCell configured with SCell index i, thewireless device may ignore the C, field. In an example, an R field mayindicate a reserved bit. The R field may be set to zero.

Example of SR

In an example, a wireless device may trigger a SR for requesting UL-SCHresource when the wireless device has new transmission. A gNB maytransmit to a wireless device at least one message comprising parametersindicating zero, one or more SR configurations. A SR configuration maycomprise a set of PUCCH resources for SR on one or more BWPs, and/or oneor more cells. On a BWP, at most one PUCCH resource for SR may beconfigured. Each SR configuration may correspond to one or more logicalchannels. Each logical channel may be mapped to zero or one SRconfiguration configured by the at least one message. A SR configurationof a logical channel (LCH) that triggers a buffer status report (BSR)may be considered as a corresponding SR configuration for a triggeredSR.

In an example, for each SR configuration, the at least one message mayfurther comprise one or more parameters indicating at least one of: a SRprohibit timer; a maximum number of SR transmission; a parameterindicating a periodicity and offset of SR transmission; and/or a PUCCHresource. In an example, the SR prohibit timer may be a duration duringwhich the wireless device may be not allowed to transmit the SR. In anexample, the maximum number of SR transmission may be a transmissionnumber for which the wireless device may be allowed to transmit the SRat most.

In an example, a PUCCH resource may be identified by at least: frequencylocation (e.g., starting PRB); a PUCCH format associated with initialcyclic shift of a base sequence and time domain location (e.g., startingsymbol index).

In an example, a wireless device may maintain a SR transmission counter(e.g., SR_COUNTER) associated with a SR configuration.

In an example, if an SR of a SR configuration is triggered, and thereare no other SRs pending corresponding to the same SR configuration, awireless device may set the SR_COUNTER of the SR configuration to afirst value (e.g., 0).

In an example, when an SR is triggered, a wireless device may considerthe SR pending until it is cancelled. In an example, when one or more ULgrants accommodate all pending data available for transmission, allpending SR(s) may be cancelled.

In an example, a wireless device may determine one or more PUCCHresources on an active BWP as valid PUCCH resources at a time of SRtransmission occasion.

In an example, a wireless device may transmit a PUCCH in a PUCCHresource associated with a SR configuration when the wireless devicetransmits a positive SR. In an example, a wireless device may transmitthe PUCCH using PUCCH format 0, or PUCCH format 1, according to thePUCCH configuration.

In an example, a wireless device may receive one or more RRC messagecomprising parameters of one or more SR configurations. In an example,for each of the one or more SR configurations, the parameters mayindicate at least one of: a SR prohibit timer; a maximum number of SRtransmission; a parameter indicating a periodicity and offset of SRtransmission; and/or a PUCCH resource identified by a PUCCH resourceindex. In an example, when a SR of a SR configuration triggered(therefore in pending now) in response to a BSR being triggered on a LCHcorresponding to the SR configuration, a wireless device may set aSR_COUNTER to a first value (e.g., 0), if there is no other pending SRscorresponding to the SR configuration.

In an example, a wireless device may determine whether there is at leastone valid PUCCH resource for the pending SR at the time of SRtransmission occasion. If there is no valid PUCCH resource for thepending SR, the wireless device may initiate a random access procedureon a PCell. The wireless device may cancel the pending SR in response tono valid PUCCH resource for the pending SR.

In an example, if there is at least one valid PUCCH resource for thepending SR, a wireless device may determine an SR transmission occasionon the at least one valid PUCCH resource based on the periodicity andthe offset of SR transmission. In an example, if the SR prohibit timeris running, the wireless device may wait for another SR transmissionoccasion. In an example, if the SR prohibit timer is not running; and ifthe at least one valid PUCCH resource for the SR transmission occasiondoes not overlap with a measurement gap; and if the at least one validPUCCH resource for the SR transmission occasion does not overlap with anuplink shared channel (UL-SCH) resource; if the SR_COUNTER is less thanthe maximum number of SR transmission, the wireless device may incrementthe SR_COUNTER (e.g., by one), instruct the physical layer of thewireless device to signal the SR on the at least one valid PUCCHresource for the SR. The physical layer of the wireless device maytransmit a PUCCH on the at least one valid PUCCH resource for the SR.The wireless device may monitor a PDCCH for detecting a DCI for uplinkgrant in response to transmitting the PUCCH.

In an example, if a wireless device receives one or more uplink grantswhich may accommodate all pending data available for transmission, thewireless device may cancel the pending SR, and/or stop the SR prohibittimer.

In an example, if the wireless device does not receive one or moreuplink grants which may accommodate all pending data available fortransmission, the wireless device may repeat one or more actionscomprising: determining the at least one valid PUCCH resource; checkingwhether the SR prohibit timer is running; whether the SR_COUNTER isequal or greater than the maximum number of SR transmission;incrementing the SR_COUNTER, transmitting the SR and starting the SRprohibit timer; monitoring a PDCCH for uplink grant.

In an example, if the SR_COUNTER indicates a number equal to or greaterthan the maximum number of SR transmission, a wireless device mayrelease PUCCH for one or more serving cells, and/or release SRS for theone or more serving cells, and/or clear one or more configured downlinkassignments and uplink grants, and/or initiate a random access procedureon a PCell, and/or cancel all the pending SRs.

Example Bandwidth Parts (BWPs)

In an example, a wireless device may be configured with one or more BWPsfor a serving cell (e.g., PCell, SCell). In an example, the serving cellmay be configured with at most a first number (e.g., four) BWPs. In anexample, for an activated serving cell, there may be one active BWP atany point in time.

In an example, a BWP switching for a serving cell may be used toactivate an inactive BWP and deactivate an active BWP at a time. In anexample, the BWP switching may be controlled by a PDCCH indicating adownlink assignment or an uplink grant. In an example, the BWP switchingmay be controlled by an inactivity timer (e.g. bwp-InactivityTimer). Inan example, the BWP switching may be controlled by a MAC entity inresponse to initiating a Random Access procedure. In an example, the BWPswitching may be controlled by an RRC signalling.

In an example, in response to RRC (re-)configuration offirstActiveDownlinkBWP-Id (e.g., included in RRC signaling) and/orfirstActiveUplinkBWP-Id (e.g., included in RRC signaling) for a servingcell (e.g., SpCell), the wireless device may activate a DL BWP indicatedby the firstActiveDownlinkBWP-Id and/or an UL BWP indicated by thefirstActiveUplinkBWP-Id, respectively without receiving a PDCCHindicating a downlink assignment or an uplink grant. In an example, inresponse to an activation of an SCell, the wireless device may activatea DL BWP indicated by the firstActiveDownlinkBWP-Id and/or an UL BWPindicated by the firstActiveUplinkBWP-Id, respectively without receivinga PDCCH indicating a downlink assignment or an uplink grant.

In an example, an active BWP for a serving cell may be indicated by RRCsignaling and/or PDCCH. In an example, for unpaired spectrum (e.g.,time-division-duplex (TDD)), a DL BWP may be paired with a UL BWP, andBWP switching may be common (e.g., simultaneous) for the UL BWP and theDL BWP.

In an example, for an active BWP of an activated serving cell (e.g.,PCell, SCell) configured with one or more BWPs, a wireless device mayperform, on the active BWP, at least one of: transmitting on UL-SCH onthe active BWP; transmitting on RACH on the active BWP if PRACHoccasions are configured; monitoring a PDCCH on the active BWP;transmitting, if configured, PUCCH on the active BWP; reporting CSI forthe active BWP; transmitting, if configured, SRS on the active BWP;receiving DL-SCH on the active BWP; (re-) initializing any suspendedconfigured uplink grants of configured grant Type 1 on the active BWPaccording to a stored configuration, if any, and to start in a symbolbased on some procedures.

In an example, for a deactivated BWP of an activated serving cellconfigured with one or more BWPs, a wireless device may not perform atleast one of: transmitting on UL-SCH on the deactivated BWP;transmitting on RACH on the deactivated BWP; monitoring a PDCCH on thedeactivated BWP; transmitting PUCCH on the deactivated BWP; reportingCSI for the deactivated BWP; transmitting SRS on the deactivated BWP,receiving DL-SCH on the deactivated BWP. In an example, for adeactivated BWP of an activated serving cell configured with one or moreBWPs, a wireless device may clear any configured downlink assignment andconfigured uplink grant of configured grant Type 2 on the deactivatedBWP; may suspend any configured uplink grant of configured Type 1 on thedeactivated (or inactive) BWP.

In an example, a base station may configure an activated serving cell ofa wireless device with a BWP inactivity timer.

In an example, the base station may configure the wireless device with adefault DL BWP ID for the activated serving cell (e.g., via RRCsignaling including defaultDownlinkBWP-Id parameter). In an example, anactive DL BWP of the activated serving cell may not be a BWP indicatedby the default DL BWP ID.

In an example, the base station may not configure the wireless devicewith a default DL BWP ID for the activated serving cell (e.g., via RRCsignaling including defaultDownlinkBWP-Id parameter). In an example, anactive DL BWP of the activated serving cell may not be an initialdownlink BWP (e.g., via RRC signaling including initialDownlinkBWPparameter) of the activated serving cell.

In an example, the BWP inactivity timer associated with the active DLBWP of the activated serving cell may expire.

In an example, the base station may configure the wireless device withthe default DL BWP ID. In an example, when the base station configuresthe wireless device with the default DL BWP ID, in response to the BWPinactivity timer expiring, a MAC entity of the wireless device mayperform BWP switching to a BWP indicated by the default DL BWP ID.

In an example, the base station may not configure the wireless devicewith the default DL BWP ID. In an example, when the base station doesnot configure the wireless device with the default DL BWP ID, inresponse to the BWP inactivity timer expiring, a MAC entity of thewireless device may perform BWP switching to the initial downlink BWP(e.g., initialDownlinkBWP in RRC signalling).

In an example, a wireless device may receive a PDCCH for a BWP switching(e.g., UL and/or DL BWP switching). In an example, a MAC entity of thewireless device may switch from a first active DL BWP of the activatedserving cell to a BWP (e.g., DL BWP) of the activated serving cell inresponse to the receiving the PDCCH. In an example, the switching fromthe first active DL BWP to the BWP may comprise setting the BWP as acurrent active DL BWP of the activated serving cell. In an example, thewireless device may deactivate the first active DL BWP in response tothe switching.

In an example, the base station may configure the wireless device with adefault DL BWP ID. In an example, the BWP may not be indicated (oridentified) by the default DL BWP ID. In an example, when the basestation configures the wireless device with the default DL BWP ID andthe MAC entity of the wireless device switches from the first active DLBWP of the activated serving cell to the BWP, the wireless device maystart or restart the BWP inactivity timer associated with the BWP (e.g.,the current active DL BWP) in response to the BWP not being the defaultDL BWP (or the BWP not being indicated by the default DL BWP ID).

In an example, the base station may not configure the wireless devicewith a default DL BWP ID. In an example, the BWP may not be the initialdownlink BWP of the activated serving cell. In an example, when the basestation does not configure the wireless device with the default DL BWPID and the MAC entity of the wireless device switches from the firstactive DL BWP of the activated serving cell to the BWP, the wirelessdevice may start or restart the BWP inactivity timer associated with theBWP (e.g., the current active DL BWP) in response to the BWP not beingthe initial downlink BWP.

In an example, when configured for operation in bandwidth parts (BWPs)of a serving cell, a wireless device (e.g., a UE) may be configured, byhigher layers with a parameter BWP-Downlink, a first set of BWPs (e.g.,at most four BWPs) for receptions, by the UE, (e.g., DL BWP set) in adownlink (DL) bandwidth for the serving cell.

In an example, when configured for operation in bandwidth parts (BWPs)of a serving cell, a wireless device (e.g., a UE) may be configured, byhigher layers with a parameter BWP-Uplink, a second set of BWPs (e.g.,at most four BWPs) for transmissions, by the UE, (e.g., UL BWP set) in auplink (UL) bandwidth for the serving cell.

In an example, the base station may provide a wireless device with ahigher layer parameter initialDownlinkBWP. In an example, an initialactive DL BWP may be provided by the higher layer parameterinitialDownlinkBWP in response to the providing.

In an example, a wireless device may have a dedicated BWP configuration.

In an example, in response to the wireless device having the dedicatedBWP configuration, the wireless device may be provided by a higher layerparameter (e.g., firstActiveDownlinkBWP-Id). The higher layer parametermay indicate a first active DL BWP for receptions.

In an example, in response to the wireless device having the dedicatedBWP configuration, the wireless device may be provided by a higher layerparameter (e.g., firstActiveUplinkBWP-Id). The higher layer parametermay indicate a first active UL BWP for transmissions on a carrier (e.g.,SUL, NUL) of a serving cell (e.g., primary cell, secondary cell).

In an example, for an unpaired spectrum operation, a DL BWP, from afirst set of BWPs, with a DL BWP index provided by a higher layerparameter bwp-Id (e.g., bwp-Id) may be linked with an UL BWP, from asecond set of BWPs, with an UL BWP index provided by a higher layerparameter bwp-Id (e.g., bwp-Id) when the DL BWP index of the DL BWP issame as the UL BWP index of the UL BWP.

In an example, a bandwidth part indicator field may be configured in aDCI format (e.g., DCI format 1_1, DCI format 0_1). In an example, avalue of the bandwidth part indicator field may indicate an active DL/ULBWP, from a first set of BWPs, for one or more DL/ULreceptions/transmissions. In an example, the bandwidth part indicatorfield may indicate a DL/UL BWP different from the active DL/UL BWP. Inan example, in response to the bandwidth part indicator field indicatingthe DL/UL BWP different from the active DL/ULBWP, the wireless devicemay set the DL/UL BWP as a current active DL/UL BWP. In an example, thesetting the DL/UL BWP as a current active DL/UL BWP may compriseactivating the DL/UL BWP and deactivating the active DL/UL BWP.

In an example, an active DL/UL BWP change may comprise switching fromthe active DL/UL BWP of a serving cell to a DL/UL BWP of the servingcell. In an example, the switching from the active DL/UL BWP to theDL/UL BWP may comprise setting the DL/UL BWP as a current active DL/ULBWP and deactivating the active DL/UL BWP.

In an example, for a serving cell (e.g., PCell, SCell), a base stationmay provide a wireless device with a higher layer parameterdefaultDownlinkBWP-Id. In an example, the higher layer parameterdefaultDownlinkBWP-Id may indicate a default DL BWP among the first setof (configured) BWPs of the serving cell.

In an example, a base station may not provide a wireless device with ahigher layer parameter defaultDownlinkBWP-Id. In response to not beingprovided by the higher layer parameter defaultDownlinkBWP-Id, thewireless device may set the initial active DL BWP as a default DL BWP.In an example, in response to not being provided by the higher layerparameter defaultDownlinkBWP-Id, the default DL BWP may be the initialactive DL BWP.

In an example, a base station may provide a wireless device with ahigher layer parameter BWP-InactivityTimer. In an example, the higherlayer parameter BWP-InactivityTimer may indicate a BWP inactivity timerwith a timer value for a serving cell (e.g., primary cell, secondarycell).

In an example, a base station may provide a wireless device with ahigher layer parameter firstActiveDownlinkBWP-Id of a serving cell(e.g., secondary cell). In an example, the higher layer parameterfirstActiveDownlinkBWP-Id may indicate a DL BWP on the serving cell(e.g., secondary cell). In an example, in response to the being providedby the higher layer parameter firstActiveDownlinkBWP-Id, the wirelessdevice may use the DL BWP as a first active DL BWP on the serving cell.

In an example, a base station may provide a wireless device with ahigher layer parameter firstActiveUplinkBWP-Id on a carrier (e.g., SUL,NUL) of a serving cell (e.g., secondary cell). In an example, the higherlayer parameter firstActiveUplinkBWP-Id may indicate an UL BWP. In anexample, in response to the being provided by the higher layer parameterfirstActiveUplinkBWP-Id, the wireless device may use the UL BWP as afirst active UL BWP on the carrier of the serving cell.

In an example, a UE may not monitor PDCCH when the UE performs RRMmeasurements over a bandwidth that is not within the active DL BWP forthe UE.

If a higher layer parameter firstActiveDownlinkBWP-Id is configured foran SpCell, a higher layer parameter firstActiveDownlinkBWP-Id indicatesan ID of a DL BWP to be activated upon performing the reconfiguration.

If a higher layer parameter firstActiveDownlinkBWP-Id is configured foran SCell, a higher layer parameter firstActiveDownlinkBWP-Id indicatesan ID of a DL BWP to be used upon MAC-activation of the SCell.

If a higher layer parameter firstActiveUplinkBWP-Id is configured for anSpCell, a higher layer parameter firstActiveUplinkBWP-Id indicates an IDof an UL BWP to be activated upon performing the reconfiguration.

If a higher layer parameter firstActiveUplinkBWP-Id is configured for anSCell, a higher layer parameter firstActiveUplinkBWP-Id indicates an IDof an UL BWP to be used upon MAC-activation of the SCell.

Example of a BFR Procedure.

FIG. 16A shows example of a first beam failure scenario. In the example,a gNB may transmit a PDCCH from a transmission (Tx) beam to a receiving(Rx) beam of a wireless device from a TRP. When the PDCCH on the beampair link (between the Tx beam of the gNB and the Rx beam of thewireless device) have a lower-than-threshold RSRP/SINR value due to thebeam pair link being blocked (e.g., by a moving car or a building), thegNB and the wireless device may start a beam failure recovery procedureon the TRP.

FIG. 16B shows example of a second beam failure scenario. In theexample, the gNB may transmit a PDCCH from a beam to a wireless devicefrom a first TRP. When the PDCCH on the beam is blocked, the gNB and thewireless device may start a beam failure recovery procedure on a newbeam on a second TRP.

In an example, a wireless device may measure quality of beam pair linkusing one or more RSs. The one or more RSs may be one or more SSBs, orone or more CSI-RS resources. A CSI-RS resource may be identified by aCSI-RS resource index (CRI). In an example, quality of beam pair linkmay be defined as a RSRP value, or a reference signal received quality(e.g. RSRQ) value, and/or a CSI (e.g., SINR) value measured on RSresources. In an example, a gNB may indicate whether an RS resource,used for measuring beam pair link quality, is QCLed (Quasi-Co-Located)with DM-RSs of a PDCCH. The RS resource and the DM-RSs of the PDCCH maybe called QCLed when the channel characteristics from a transmission onan RS to a wireless device, and that from a transmission on a PDCCH tothe wireless device, are similar or same under a configured criterion.In an example, The RS resource and the DM-RSs of the PDCCH may be calledQCLed when doppler shift and/or doppler shift of the channel from atransmission on an RS to a wireless device, and that from a transmissionon a PDCCH to the wireless device, are same.

In an example, a gNB may transmit one or more messages comprisingconfiguration parameters of an uplink physical channel or signal fortransmitting a beam failure recovery request. The uplink physicalchannel or signal may be based on one of: a contention-free PRACH(BFR-PRACH), which may be a resource orthogonal to resources of otherPRACH transmissions; a PUCCH (BFR-PUCCH); a PUSCH (e.g., BFR MAC-CE)and/or a contention-based PRACH resource (CF-PRACH). Combinations ofthese candidate signal/channels may be configured by the gNB. In anexample, when configured with multiple resources for a BFR signal, awireless device may autonomously select a first resource fortransmitting the BFR signal. In an example, when configured with aBFR-PRACH resource, a BFR-PUCCH resource, and a CF-PRACH resource, thewireless device may select the BFR-PRACH resource for transmitting theBFR signal. In an example, when configured with a BFR-PRACH resource, aBFR-PUCCH resource, and a CF-PRACH resource, the gNB may transmit amessage to the wireless device indicating a resource for transmittingthe BFR signal.

Example of a BFR Procedure.

FIG. 17 shows an example flowchart of a BFR procedure. A wireless devicemay receive one or more RRC messages comprising BFR parameters. The oneor more RRC messages may comprise an RRC message (e.g. RRC connectionreconfiguration message, or RRC connection reestablishment message, orRRC connection setup message). The wireless device may detect at leastone beam failure according to at least one of BFR parameters. Thewireless device may start a first timer if configured in response todetecting the at least one beam failure. The wireless device may selecta selected beam in response to detecting the at least one beam failure.The selected beam may be a beam with good channel quality (e.g., RSRP,SINR, or BLER) from a set of candidate beams. The candidate beams may beidentified by a set of reference signals (e.g., SSBs, or CSI-RSs). Thewireless device may transmit at least a first BFR signal to a gNB inresponse to the selecting the selected beam. The at least first BFRsignal may be associated with the selected beam. The at least first BFRsignal may be a preamble transmitted on a PRACH resource, or a beamfailure recovery request (e.g., similar to scheduling request) signaltransmitted on a PUCCH resource, or a beam indication (e.g., BFR MAC CE)transmitted on a PUSCH resource. The wireless device may transmit the atleast first BFR signal with a transmission beam corresponding to areceiving beam associated with the selected beam. The wireless devicemay start a response window in response to transmitting the at leastfirst BFR signal. In an example, the response window may be a timer witha value configured by the gNB. When the response window is running, thewireless device may monitor a PDCCH in a first coreset (e.g., UEspecific or dedicated to the wireless device or wireless devicespecific). The first coreset may be associated with the BFR procedure.In an example, the wireless device may monitor the PDCCH in the firstcoreset in response to transmitting the at least first BFR signal. Thewireless device may receive a first DCI via the PDCCH in the firstcoreset when the response window is running. The wireless device mayconsider the BFR procedure successfully completed when receiving thefirst DCI via the PDCCH in the first coreset before the response windowexpires. The wireless device may stop the first timer if configured inresponse to the BFR procedure successfully being completed. The wirelessdevice may stop the response window in response to the BFR proceduresuccessfully being completed.

In an example, when the response window expires, and the wireless devicedoes not receive the DCI, the wireless device may increment atransmission number, wherein, the transmission number is initialized toa first number (e.g., 0, 1) before the BFR procedure is initiated. Ifthe transmission number indicates a number less than the configuredmaximum transmission number, the wireless device may repeat one or moreactions comprising at least one of: a BFR signal transmission; startingthe response window; monitoring the PDCCH; incrementing the transmissionnumber if no response received during the response window is running. Ifthe transmission number indicates a number equal or greater than theconfigured maximum transmission number, the wireless device may declarethe BFR procedure is unsuccessfully completed.

Example of BFR Procedure

In an example, a wireless device may trigger a beam failure recovery byinitiating a random-access procedure on a primary cell based ondetecting a beam failure. In an example, a wireless device may select asuitable/candidate beam for a beam failure recovery based on detecting abeam failure. In an example, the wireless device may determine that thebeam failure recovery is complete based on completion of therandom-access procedure.

FIG. 18 shows an example of a downlink beam failure recovery procedureas per an aspect of an embodiment of the present disclosure.

In an example, a base station may configure a medium-access control(MAC) entity of a wireless device with a beam failure recovery procedureby an RRC. The wireless device may detect a beam failure based on one ormore first RSs (e.g., SSB, CSI-RS). The beam failure recovery proceduremay be used for indicating to the base station of a candidate RS (e.g.,SSB or CSI-RS) when the wireless device detects the beam failure. In anexample, the wireless device may detect the beam failure based oncounting a beam failure instance indication from a lower layer of thewireless device (e.g. PHY layer) to the MAC entity.

In an example, a base station may reconfigure an information element(IE) beamFailureRecoveryConfig during an ongoing random-access procedurefor a beam failure recovery. In response to the reconfiguring the IEbeamFailureRecoveryConfig, the MAC entity may stop the ongoingrandom-access procedure. Based on the stopping the ongoing random-accessprocedure, the wireless device may initiate a second random-accessprocedure for the beam failure recovery using/with the reconfigured IEbeamFailureRecoveryConfig.

In an example, an RRC may configure a wireless device with one or moreparameters in an IE BeamFailureRecoveryConfig and an IERadioLinkMonitoringConfig for a beam failure detection and recoveryprocedure. The one or more parameters may comprise at least:beamFailureInstanceMaxCount for a beam failure detection;beamFailureDetectionTimer for the beam failure detection;beamFailureRecoveryTimer for a beam failure recovery; rsrp-ThresholdSSB:an RSRP threshold for the beam failure recovery; PowerRampingStep forthe beam failure recovery; powerRampingStepHighPriority for the beamfailure recovery; preambleReceivedTargetPower for the beam failurerecovery; preambleTransMax for the beam failure recovery;scalingFactorBI for the beam failure recovery; ssb-perRACH-Occasion forthe beam failure recovery; ra-OccasionList for the beam failurerecovery; ra-ssb-OccasionMaskIndex for the beam failure recovery;prach-ConfigurationIndex for the beam failure recovery; andra-ResponseWindow. The ra-ResponseWindow may be a time window to monitorat least one response (e.g., random-access response, BFR response) forthe beam failure recovery. In an example, the wireless device may use acontention-free random-access preamble for the beam failure recovery.

FIG. 18 shows an example of a beam failure instance (BFI) indication. Inan example, a wireless device may use at least one UE variable for abeam failure detection. In an example, BFI_COUNTER may be one of the atleast one UE variable. The BFI_COUNTER may be a counter for a beamfailure instance indication. The wireless device may set the BFI_COUNTERinitially to zero.

In an example, a MAC entity of a wireless device may receive a beamfailure instance (BFI) indication from a lower layer (e.g. PHY) of thewireless device. Based on the receiving the BFI indication, the MACentity of the wireless device may start or restart thebeamFailureDetectionTimer (e.g., BFR timer in FIG. 18). Based on thereceiving the BFI indication, the MAC entity of the wireless device mayincrement BFI_COUNTER by one (e.g., at time T, 2T, 5T in FIG. 18).

In an example, the BFI_COUNTER may be equal to or greater than thebeamFailureInstanceMaxCount. Based on the BFI_COUNTER being equal to orgreater than the beamFailureInstanceMaxCount, the MAC entity of thewireless device may initiate a random-access procedure (e.g. on anSpCell) for a beam failure recovery.

In an example, in FIG. 18, the wireless device may initiate therandom-access procedure at time 6T, when the BFI_COUNTER is equal to orgreater than the beamFailureInstanceMaxCount (e.g., 3).

In an example, the wireless device may select an uplink carrier (e.g.,SUL, NUL) to perform the random-access procedure for the beam failurerecovery. In an example, the base station may configure an active uplinkBWP of the selected uplink carrier with IE beamFailureRecoveryConfig.When the wireless device initiates the random-access procedure for thebeam failure recovery, based on the active uplink BWP of the selecteduplink carrier being configured with the IE beamFailureRecoveryConfig,the wireless device may start, if configured, thebeamFailureRecoveryTimer. When the wireless device initiates therandom-access procedure for the beam failure recovery, based on theactive uplink BWP of the selected uplink carrier being configured withthe IE beamFailureRecoveryConfig, the wireless device may apply one ormore parameters (e.g., powerRampingStep, preambleReceivedTargetPower,and preambleTransMax) configured in the IE BeamFailureRecoveryConfig forthe random-access procedure.

In an example, the base station may configurepowerRampingStepHighPriority in the IE beamFailureRecoveryConfig. Whenthe wireless device initiates the random-access procedure for the beamfailure recovery and the active uplink BWP of the selected uplinkcarrier is configured with the IE beamFailureRecoveryConfig, based onthe powerRampingStepHighPriority being configured in the IEbeamFailureRecoveryConfig, the wireless device may setPREAMBLE_POWER_RAMPING_STEP to the powerRampingStepHighPriority.

In an example, the base station may not configurepowerRampingStepHighPriority in the IE beamFailureRecoveryConfig. Whenthe wireless device initiates the random-access procedure for the beamfailure recovery and the active uplink BWP of the selected uplinkcarrier is configured with the IE beamFailureRecoveryConfig, based onthe powerRampingStepHighPriority not being configured in the IEbeamFailureRecoveryConfig, the wireless device may setPREAMBLE_POWER_RAMPING_STEP to the powerRampingStep.

In an example, the base station may configure scalingFactorBI in the IEbeamFailureRecoveryConfig. When the wireless device initiates therandom-access procedure for the beam failure recovery and the activeuplink BWP of the selected uplink carrier is configured with the IEbeamFailureRecoveryConfig, based on the scalingFactorBI being configuredin the IE beamFailureRecoveryConfig, the wireless device may setSCALING_FACTOR_BI to the scalingFactorBI.

In an example, the base station may configure the active uplink BWP ofthe selected uplink carrier with the IE beamFailureRecoveryConfig. Basedon the active uplink BWP of the selected uplink carrier being configuredwith the IE beamFailureRecoveryConfig, the random-access procedure maybe a contention-free random-access procedure.

In an example, the base station may not configure the active uplink BWPof the selected uplink carrier with the IE beamFailureRecoveryConfig.Based on the active uplink BWP of the selected uplink carrier not beingconfigured with the IE beamFailureRecoveryConfig, the random-accessprocedure may be a contention-based random-access procedure.

In an example, the beamFailureDetectionTimer may expire. Based on thebeamFailureDetectionTimer expiring, the MAC entity of the wirelessdevice may set the BFI_COUNTER to zero (e.g., in FIG. 18, between time3T and 4T).

In an example, a base station may configure a wireless device with oneor more first RSs (e.g., SS/PBCH block, CSI-RS, etc.) for a beam failuredetection (e.g., by RadioLinkMonitoringRS in the IERadioLinkMonitoringConfig). In an example, the base station mayreconfigure the beamFailureDetectionTimer or thebeamFailureInstanceMaxCount or at least one RS of the one or more firstRSs by higher layers (e.g., RRC). Based on the reconfiguring, the MACentity of the wireless device may set the BFI_COUNTER to zero.

In an example, the wireless device may complete the random-accessprocedure (e.g., contention-free random-access or contention-basedrandom-access) for the beam failure recovery successfully. Based on thecompleting the random-access procedure successfully, the wireless devicemay determine/consider that the beam failure recovery is successfullycompleted.

In an example, the wireless device may complete the random-accessprocedure for the beam failure recovery successfully. Based on thecompleting the random-access procedure successfully, the wireless devicemay, if configured, stop the beamFailureRecoveryTimer. Based on thecompleting the random-access procedure successfully, the wireless devicemay set the BFI_COUNTER to zero.

In an example, the beamFailureRecoveryTimer may be running. In anexample, the base station may not configure the wireless device with thebeamFailureRecoveryTimer. In an example, the base station may providethe wireless device with one or more second RSs (e.g., SS/PBCH blocks,periodic CSI-RSs, etc.) for a beam failure recovery by a higher layerparameter candidateBeamRSList in the IE beamFailureRecoveryConfig. In anexample, the base station may provide the wireless device with one ormore uplink resources (e.g., contention-free random-access resources)for a beam failure recovery request (BFRQ) used in the beam failurerecovery by a higher layer (e.g., RRC) parameter (e.g.,candidateBeamRSList, ssb-perRACH-Occasion, ra-ssb-OccasionMaskIndex inthe IE beamFailureRecoveryConfig). An uplink resource of the one or moreuplink resources may be associated with a candidate RS (e.g., SSB,CSI-RS) of the one or more second RSs. In an example, the associationbetween the uplink resource and the candidate RS may be one-to-one.

In an example, at least one RS among the one or more second RSs may havea RSRP (e.g., SS-RSRP, CSI-RSRP) higher than a second threshold (e.g.,rsrp-ThresholdSSB, rsrp-ThresholdCSI-RS). In an example, the wirelessdevice may select a candidate RS among the at least one RS for the beamfailure recovery.

In an example, the candidate RS may be a CSI-RS. In an example, theremay be no ra-PreambleIndex associated with the candidate RS. Based onthe candidate RS being the CSI-RS and no ra-PreambleIndex beingassociated with the candidate RS, the MAC entity of the wireless devicemay set PREAMBLE_INDEX to an ra-PreambleIndex. The ra-PreambleIndex maybe associated/corresponding to an SSB in the one or more second RSs(e.g., indicated candidateBeamRSList). The SSB may be quasi-collocatedwith the candidate RS.

In an example, the candidate RS may be a CSI-RS and there may bera-PreambleIndex associated with the candidate RS. In an example, thecandidate RS may be an SSB. The MAC entity of the wireless device mayset PREAMBLE_INDEX to a ra-PreambleIndex, associated/corresponding tothe candidate RS, from a set of random-access preambles for the BFRQ. Inan example, a higher layer (RRC) parameter may configure the set ofrandom-access preambles for the BFRQ for the random-access procedure forthe beam failure recovery.

In an example, a MAC entity of a wireless device may transmit an uplinksignal (e.g., contention-free random-access preamble) for the BFRQ.Based on the transmitting the uplink signal, the MAC entity may start aresponse window (e.g., ra-ResponseWindow configured in the IEBeamFailureRecoveryConfig) at a first PDCCH occasion from the end of thetransmitting the uplink signal. Based on the transmitting the uplinksignal, the wireless device may, while the response window is running,monitor at least one PDCCH on a search space indicated byrecoverySearchSpaceId (e.g. of an SpCell) for a DCI. The DCI may beidentified by an RNTI (e.g., C-RNTI, MCS-C-RNTI) of the wireless device.

In an example, the MAC entity of the wireless device may receive, from alower layer (e.g., PHY) of the wireless device, a notification of areception of the DCI on the search space indicated by therecoverySearchSpaceId. In an example, the wireless device may receivethe DCI on a serving cell. In an example, the wireless device maytransmit the uplink signal via the serving cell. In an example, the DCImay be addressed to the RNTI (e.g., C-RNTI) of the wireless device. Inan example, based on the receiving the notification and the DCI beingaddressed to the RNTI, the wireless device may determine/consider therandom-access procedure being successfully completed.

In an example, the wireless device may transmit the uplink signal on anSpCell. In an example, the response window configured in the IEBeamFailureRecoveryConfig may expire. In an example, the wireless devicemay not receive a DCI (or a PDCCH transmission) addressed to the RNTI ofthe wireless device on the search space indicated byrecoverySearchSpaceId on the serving cell (e.g., before the responsewindow expires). Based on the response window expiring and not receivingthe DCI, the wireless device may consider a reception of a random-accessresponse (e.g., BFR response) unsuccessful. Based on the response windowexpiring and not receiving the DCI, the wireless device may increment atransmission counter (e.g., PREAMBLE_TRANSMISSION_COUNTER) by one. In anexample, the transmission counter may be equal to preambleTransMax plusone. Based on the transmission counter being equal to thepreambleTransMax plus one and transmitting the uplink signal on theSpCell, the wireless device may indicate a random-access problem toupper layers (e.g., RRC).

In an example, the MAC entity of the wireless device may stop theresponse window (and hence monitoring for the random access response)after successful reception of the random-access response (e.g., the DCIaddressed to the RNTI of the wireless device, BFR response) in responseto the random access response comprising a random access preambleidentifier that matches the transmitted PREAMBLE_INDEX.

In an example, based on completion of a random-access procedure, a MACentity of a wireless device may discard explicitly signaledcontention-free random-access resources except one or more uplinkresources (e.g., contention-free random-access resources) for BFRQ.

Example of BFR Procedure

In an example, a base station may provide a wireless device, for aserving cell (e.g., primary cell, secondary cell), with a first set ofresource configuration indexes (e.g., periodic CSI-RS resourceconfiguration indexes) by a higher layer parameterfailureDetectionResources (e.g., explicit beam failure detectionconfiguration). The first set of resource configuration indexes mayindicate one or more first RSs (e.g., CSI-RS, SS/PBCH block, etc.). Thebase station may configure the higher layer parameterfailureDetectionResources for a downlink BWP (of configured downlinkBWPs) of the serving cell. In an example, the base station may providethe wireless device, for the serving cell, with a second set of resourceconfiguration indexes (e.g., periodic CSI-RS resource configurationindexes, SS/PBCH block indexes) by a higher layer parametercandidateBeamRSList. The second set of resource configuration indexesmay indicate one or more second RSs (e.g., CSI-RS, SS/PBCH block, etc.).The base station may configure the higher layer parametercandidateBeamRSList for an uplink BWP (of configured uplink BWPs) of theserving cell. In an example, the wireless device may use the one or morefirst RSs and/or the one or more second RSs for radio link qualitymeasurements on the serving cell.

In an example, a base station may not provide a wireless device with ahigher layer parameter failureDetectionResources. Based on not beingprovided with the higher layer parameter failureDetectionResources, thewireless device may determine a first set of resource configurationindexes to include a resource configuration index (e.g., periodic CSI-RSresource configuration indexes) (e.g., implicit beam failure detectionconfiguration). In an example, the resource configuration index may besame as an RS index in a RS set. In an example, the RS index may beindicated by a TCI state (e.g., via a higher layer parameter TCI-state).In an example, the TCI state may be used for a control resource set(coreset) that the wireless device is configured to monitor at least onePDCCH. In an example, the base station may configure the TCI state forthe coreset. In an example, the TCI state may comprise two RS indexes.Based on the TCI state comprising two RS indexes, the first set ofresource configuration indexes may include an RS index, of the two RSindexes, with QCL-TypeD configuration. In an example, the base stationmay configure the TCI state for the coreset.

In an example, the wireless device may expect the first set of resourceconfiguration indexes to include up to two RS indexes. The wirelessdevice may expect a single port RS in the first set of resourceconfiguration indexes. In an example, the one or more first RSs maycomprise up to two RSs indicated by the two RS indexes.

In an example, a first threshold (e.g. Qout,LR) may correspond to adefault value of higher layer parameter rlmInSyncOutOfSyncThreshold. Inan example, a second threshold (e.g. Qin,LR) may correspond to a valueprovided by higher layer parameter rsrp-ThresholdSSB in the IEBeamFailureRecoveryConfig.

In an example, a physical layer in a wireless device may assess a firstradio link quality of the one or more first RSs (or the first set ofresource configuration indexes) against the first threshold. In anexample, a first RS of the one or more first RSs may be associated (e.g.quasi co-located) with at least one DM-RS of a PDCCH monitored by thewireless device.

In an example, the wireless device may apply the second threshold to afirst L1-RSRP measurement obtained from a SS/PBCH block of the one ormore second RSs (or the second set of resource configuration indexes).In an example, the wireless device may apply the second threshold to asecond L1-RSRP measurement obtained from a CSI-RS of the one or moresecond RSs (or the second set of resource configuration indexes) afterscaling a reception power of the CSI-RS with a value provided by ahigher layer parameter powerControlOffsetSS.

In an example, a wireless device may assess the first radio link qualityof the one or more first RSs (indicated by the first set of resourceconfiguration indexes). A physical layer in the wireless device mayprovide a BFI indication to a higher layer (e.g. MAC) of the wirelessdevice when the first radio link quality is worse than the firstthreshold. In non-DRX mode operation, when the first radio link qualityis worse than the first threshold, the physical layer may inform thehigher layer with a first periodicity. The wireless device may determinethe first periodicity by the maximum between a shortest periodicityamong one or more periodicities of the one or more first RSs (e.g.,resource configurations in the first set) and a first value (e.g. 2msec). The first periodicity may be defined as max (the first value,TBFD-RS,M), where TBFD-RS,M is the shortest periodicity.

In an example, in DRX mode operation, when the first radio link qualityis worse than the first threshold, the physical layer may inform thehigher layer with a second periodicity. N an example, the base stationmay configure the wireless device with a DRX_cycle_length for the DRXmode operation. The wireless device may determine the second periodicityby max (1.5*DRX_cycle_length, 1.5*TBFD-RS,M) when the DRX_cycle_lengthis less than or equal to 320 ms. The wireless device may determine thatthe second periodicity is equal to the DRX_cycle_length when theDRX_cycle_length is greater than 320 ms.

In an example, based on a request from a higher layer (e.g. MAC) of thewireless device, the wireless device may provide to the higher layer oneor more candidate RSs (e.g., the periodic CSI-RS configuration indexes,the SS/PBCH blocks indexes) from the one or more second RSs (e.g., thesecond set) and one or more L1-RSRP measurements. In an example, eachcandidate RS of the one or more candidate RSs may be associated with aL1-RSRP measurement of the one or more L1-RSRP measurements. In anexample, the association may be one-to-one. In an example, the one ormore L1-RSRP measurements associated with the one or more candidate RSsmay be larger than or equal to the second threshold. In an example, thehigher layer may select a candidate RS (e.g., periodic CSI-RS resourceconfiguration, SS/PBCH block) among the one or more candidate RSs. In anexample, the candidate RS may be identified by a first RS index of thesecond set of resource configuration indexes. In an example, the firstRS index may indicate the candidate RS.

In an example, a wireless device may be provided/configured with acontrol resource set (coreset) through a link to a search space set. Thecoreset may be UE specific or dedicated to the wireless device orwireless device specific. In an example, the wireless device may monitorthe coreset for a beam failure recovery. In an example, the base stationmay provide the wireless device with the search space set by a higherlayer parameter recoverySearchSpaceId in the IEBeamFailureRecoveryConfig. The wireless device may monitor at least onePDCCH in the control resource set.

In an example, the base station may provide the wireless device with thehigher layer parameter recoverySearchSpaceId. Based on being providedwith the higher layer parameter recoverySearchSpaceId, the wirelessdevice may not expect to be provided with a second search space set formonitoring at least one PDCCH in the coreset. In an example, the coresetmay be associated with the search space set provided by the higher layerparameter recoverySearchSpaceId. Based on the coreset being associatedwith the search space set provided by the higher layer parameterrecoverySearchSpaceId, the wireless device may not expect that thecoreset is associated with a second search space set.

In an example, the base station may provide the wireless device with aconfiguration for a transmission of an uplink signal (e.g., a PRACHtransmission) by a higher layer parameter PRACH-ResourceDedicatedBFR inthe IE BeamFailureRecoveryConfig. Based on the transmission of theuplink signal (e.g., the PRACH transmission) in a first slot (e.g., slotn) and, the wireless device, starting from a second slot (e.g., slotn+4), may monitor at least one PDCCH in a search space set (e.g.,provided by the higher layer parameter recoverySearchSpaceId) fordetection of a DCI format within a response window (e.g.,ra-responseWindow). In an example, the wireless device may monitor theat least one PDCCH in the search space set (or coreset) according toantenna port quasi co-location parameters associated with the candidateRS (provided by the higher layer). In an example, the response windowmay be configured by the IE BeamFailureRecoveryConfig. The DCI formatmay be configured with CRC scrambled by a RNTI (e.g., C-RNTI,MCS-C-RNTI).

In an example, when the wireless device monitors at least one PDCCH inthe search space set (e.g., provided by the higher layer parameterrecoverySearchSpaceId) and for a reception of corresponding PDSCH, thewireless device may assume that antenna port quasi-collocationparameters for the at least one PDCCH and the corresponding PDSCH aresame as the candidate RS until the wireless device receives, by higherlayers, an activation for a TCI state or a higher layer parameterTCI-StatesPDCCH-ToAddlist and/or a higher layer parameterTCI-StatesPDCCH-ToReleaseList. In an example, a DCI format received inthe search space set while monitoring the at least one PDCCH mayschedule the corresponding PDSCH.

In an example, after the wireless device detects the DCI format with CRCscrambled by the RNTI (e.g., C-RNTI or MCS-C-RNTI) in the search spaceset (e.g., provided by the higher layer parameterrecoverySearchSpaceId), the wireless device may continue to monitor atleast one PDCCH in the search space set until the wireless devicereceives an activation command (e.g., MAC CE) for a TCI state or ahigher layer parameter TCI-StatesPDCCH-ToAddlist and/or a higher layerparameter TCI-StatesPDCCH-ToReleaseList.

In an example, the wireless device may perform the transmission of theuplink signal (e.g., PRACH transmission) on a serving cell (e.g., PCell,SCell). In an example, the wireless device may use a spatial filter forthe transmission of the uplink signal (e.g., preamble transmission forthe PRACH transmission). In an example, the wireless device may detect aDCI format, with CRC scrambled by the RNTI, in at least one PDCCH in thesearch space set (e.g., provided by the higher layer parameterrecoverySearchSpaceId). In an example, after a first number of symbols(e.g., 28 symbols) from a last symbol of a reception of the at least onePDCCH, the wireless device may transmit a second uplink signal via PUCCHon the serving cell using the spatial filter used for the transmissionof the uplink signal (e.g., the PRACH transmission) until the wirelessdevice receives an activation command (e.g., MAC CE) forPUCCH-Spatialrelationinfo or is provided PUCCH-Spatialrelationinfo forPUCCH resource(s) for the serving cell.

In an example, after a first number of symbols (e.g., 28 symbols) from alast symbol of a reception of the at least one PDCCH, the wirelessdevice may assume that antenna port quasi-collocation parameters for acoreset with index zero (e.g., Coreset 0) are same as the candidate RSfor PDCCH monitoring in the coreset with index zero.

In an example, the base station may not provide the wireless device iswith a higher layer parameter recoverySearchSpaceId. Based on not beingprovided with the higher layer parameter recoverySearchSpaceId, thewireless device may not initiate a contention-free random accessprocedure for a beam failure recovery. In an example, the wirelessdevice may initiate a contention-based random-access procedure for abeam failure recovery based on not being provided with the higher layerparameter recoverySearchSpaceId.

In an example, a wireless device may assess a downlink link quality of aserving cell based on one or more first RSs (e.g., periodic CSI-RS, SSB,etc.) in the first set of resource configuration indexes to detect abeam failure instance (BFI).

A wireless device may estimate a first radio link quality for an RS ofthe one or more first RSs and compare the first radio link quality to afirst threshold (Qout_LR) to access downlink radio link quality of theserving cell. The first threshold may be defined as a level at which adownlink radio level link may not be reliably received. In an example,the first threshold may correspond to a first percent (e.g., 10%) blockerror rate (BLER) of a hypothetical PDCCH transmission.

In an example, a wireless device may perform L1-RSRP measurements basedon one or more second RSs (e.g., periodic CSI-RS, SSB, etc.) in thesecond set of resource configuration indexes in order to detectcandidate beam (or candidate RS). An L1-RSRP measurement of thecandidate beam (or candidate RS) may be better than a second threshold(e.g., indicated by higher layer parameter rsrp-ThresholdSSB,rsrp-ThresholdCSI-rs (rsrp-ThresholdSSB+powerControlOffsetSS). UE is notrequired to perform candidate beam detection outside the active DL BWP.

A wireless device may perform a L1-RSRP measurement for an RS of the oneor more second RSs and compare the L1-RSRP measurement to the secondthreshold (rsrp-ThresholdSSB, rsrp-ThresholdCSI-rs) to select at leastone candidate beam (or candidate RS) for a beam failure recovery.

In an example, a wireless device may be active on a first DL BWP of aserving cell. The first DL BWP may be an active DL BWP of the servingcell based on being active on the first DL BWP. In an example, thewireless device may not perform a beam failure detection outside theactive DL BWP. In an example, the wireless device may not perform acandidate beam detection outside the active DL BWP. In an example, asecond DL BWP of the serving cell may be deactivated. The wirelessdevice may not perform a beam failure detection for the second DL BWPbased on the second DL BWP being deactivated. The wireless device maynot perform a candidate beam detection for the second DL BWP based onthe second DL BWP being deactivated.

In an example, a wireless device may estimate a first radio link qualityof a CSI-RS with a first subcarrier spacing (SCS) for a beam failuredetection. In an example, a wireless device may estimate a second radiolink quality of a SSB with a second subcarrier spacing (SCS) for a beamfailure detection. In an example, the wireless device may not performbeam failure detection measurements based on the first SCS and thesecond SCS being different. In an example, the wireless device may notperform beam failure detection measurements based on the CSI-RS and theSSB being frequency division multiplexes (FDM-ed) in at least one symbol(e.g., OFDM).

Example of a Beam Failure on SCell

In existing beam failure recovery (BFR) procedures, a wireless devicemay perform a BFR procedure on an SpCell (e.g., PCell or PSCell). In anexample, a base station may transmit, to a wireless device, one or moremessages comprising configuration parameters of one or more cells. Theone or more cells may comprise at least one PCell/PSCell and one or moreSCells. In an example, an SpCell (e.g., PCell or PSCell) and one or moreSCells may operate on different frequencies and/or different bands.

In an example, an SCell of the one or more SCells may support amulti-beam operation. In the multi-beam operation, a wireless device mayperform one or more beam management procedures (e.g., a BFR procedure)on/for the SCell. The wireless device may perform a BFR procedure forthe SCell when at least one of one or more beam pair links between theSCell and the wireless device fails. Existing BFR procedures may resultin inefficiencies when there is a beam failure for the SCell. ExistingBFR procedures may be inefficient, take a long time, or increase batterypower consumption.

Example embodiments enhance existing BFR procedures to improve downlinkradio efficiency and reduce uplink signaling overhead when there is abeam failure for one or more SCells. For example, an example enhancedprocess uses a first cell random access resources when a beam failurefor an SCell of the one or more SCells occurs. In an example, downlinksignaling processes are enhanced for recovery of a beam failure for anSCell. In an example, uplink signaling is enhanced for a BFR procedureof the SCell.

Example embodiments provide processes for a wireless device and a basestation to enhance a BFR procedure for an SCell. Example embodiments mayreduce a duration of the BFR procedure and may reduce battery powerconsumption.

In an example, a wireless device may be configured with an SCell by abase station. The SCell may not have uplink resources. The SCell maycomprise downlink-only resources. When the wireless device detects abeam failure on the SCell. the wireless device may not transmit anuplink signal (e.g., preamble) for a BFR procedure of the SCell on theSCell in response to not having uplink resources. The wireless devicemay not perform a BFR procedure on the SCell. The base station may notbe aware of the beam failure on the SCell in response to the wirelessdevice not performing the BFR procedure. An example embodiment enhancesBFR procedures when an SCell comprises downlink-only resources.

In an example, an SCell may operate in a high frequency (e.g. 23 GHz, 60GHz, 70 GHz). In an example, an SpCell may operate in a low frequency(e.g. 2.4 GHz, 5 GHz). The channel condition of the SCell may bedifferent from the channel condition of the SpCell. The wireless devicemay use uplink resources of the SpCell to transmit a preamble for a beamfailure recovery request for the SCell, to improve robustness oftransmission of the preamble. An example embodiment enhances BFRprocedures when an SCell operates in a different frequency than PCell.An example embodiment enhances BFR procedures when an SCell used uplinkresources (e.g., random access resources, PUCCH resources, PUSCHresources, uplink BWPs of the PCell) of the PCell for a BFR procedure ofthe SCell.

FIG. 19 shows an example of a downlink beam failure recovery procedureof a secondary cell as per an aspect of an embodiment of the presentdisclosure.

In an example, a wireless device may receive, from a base station, oneor more messages (at time T0 in FIG. 19). The one or more messages maycomprise one or more configuration parameters for a plurality of cells.The plurality of cells may comprise a first cell (e.g., PCell, PSCell,PUCCH SCell, SCell) and one or more secondary cells. The one or moresecondary cells may comprise a second cell (e.g., SCell, SCellconfigured with PUCCH).

In an example, the one or more messages may comprise one or more RRCmessages (e.g. RRC connection reconfiguration message, or RRC connectionreestablishment message, or RRC connection setup message).

In an example, the one or more configuration parameters may indicatecell-specific indices (e.g., provided by a higher layer parameterservCellIndex) for the plurality of cells. In an example, each cell ofthe plurality of cells may be identified by a respective onecell-specific index of the cell-specific indices. In an example, thefirst cell may be identified by a first cell-specific index of thecell-specific indices. In an example, the second cell may be identifiedby a second cell-specific index of the cell-specific indices.

In an example, the one or more configuration parameters may comprisebandwidth part (BWP) configuration parameters for a plurality of BWPs.The plurality of BWPs may comprise a first plurality of DL BWPs of thefirst cell and/or a first plurality of UL BWPs of the first cell. In anexample, the plurality of BWPs may comprise a second plurality of DLBWPs of the second cell and/or a second plurality of UL BWPs of thesecond cell. In an example, the first plurality of DL BWPs may comprisea first downlink BWP of the first cell. In an example, the firstplurality of UL BWPs may comprise a first uplink BWP of the first cell.In an example, the second plurality of DL BWPs may comprise a seconddownlink BWP of the second cell. In an example, the second plurality ofUL BWPs may comprise a second uplink BWP of the second cell.

In an example, the one or more configuration parameters may furthercomprise BWP specific indices for the plurality of BWPs. In an example,each BWP of the plurality of BWPs may be identified by a respective oneBWP specific index of the BWP specific indices (e.g., provided by ahigher layer parameter bwp-ID in the one or more configurationparameters).

In an example, the first downlink BWP may be identified by a first BWPspecific index of the BWP specific indices. The second downlink BWP maybe identified by a second BWP specific index of the BWP specificindices.

In an example, the one or more configuration parameters (e.g., RRC (BFR)in FIG. 19) may indicate one or more first RSs (e.g.,RadioLinkMonitoringRS provided in an IE RadioLinkMonitoringConfig) forthe second downlink BWP of the second cell (e.g., explicit BFDconfiguration).

In an example, for both explicit BFD configuration and the implicit BFDconfiguration, at least one RS of the one or more first RSs may betransmitted/configured on/in the first cell. In an example, for bothexplicit BFD configuration and the implicit BFD configuration, at leastone RS of the one or more first RSs may be transmitted/configured on/inthe second cell. In an example, for both explicit BFD configuration andthe implicit BFD configuration, at least one RS of the one or more firstRSs may be transmitted/configured on/in at least one of the one or moresecondary cells. In an example, transmitting/configuring the at leastone RS on the first cell and/or the at least one of the one or moresecondary cells may save overhead and save complexity of the wirelessdevice for tracking a high number of RSs.

In an example, at least one RS of the one or more first RSs may betransmitted/configured on/in the first cell. In an example, the secondcell and the first cell may share the at least one RS based on operatingin intra-band and/or QCL-ed (e.g., cross-carrier QCL) and/or based onsharing similar channel characteristics (e.g., Doppler spread, spatialfilter, etc.).

In an example, at least one RS of the one or more first RSs may betransmitted/configured on/in the second cell.

In an example, at least one RS of the one or more first RSs may betransmitted/configured on/in the at least one of the one or moresecondary cells. In an example, the second cell and the at least one ofthe one or more secondary cells may share the at least one RS based onoperating in intra-band and/or QCL-ed (e.g., cross-carrier QCL) and/orbased on sharing similar channel characteristics (e.g., Doppler spread,spatial filter, etc.).

In an example, the one or more first RSs may comprise one or more firstCSI-RSs. In an example, the one or more first RSs may comprise one ormore first SS/PBCH blocks. In an example, the one or more configurationparameters may indicate a maximum beam failure instance (BFI) counter(e.g., beamFailureInstanceMaxCount) (e.g., for the second cell, or forthe first cell or for the second downlink BWP of the second cell). In anexample, the wireless device may assess the one or more first RSs todetect a beam failure for the second downlink BWP of the second cell. Inan example, the one or more configuration parameters may indicate afirst threshold (e.g., provided by rlmInSyncOutOfSyncThreshold, Qout,LR)(e.g., for the second cell, or for the first cell or for the seconddownlink BWP of the second cell).

In an example, the one or more configuration parameters may indicate oneor more second RSs (e.g., candidateBeamRSList provided in IEBeamFailureRecoveryConfig) for the second downlink BWP of the secondcell. In an example, the wireless device may assess the one or moresecond RSs to select a candidate RS among the one or more second RSs fora beam failure recovery procedure of the second downlink BWP of thesecond cell.

In an example, the one or more second RSs may comprise one or moresecond CSI-RSs. In an example, the one or more second RSs may compriseone or more second SS/PBCH blocks.

In an example, the one or more configuration parameters may indicateRS-specific indices (e.g., provided by a higher layer parameterssb-index) for the one or more second RSs. In an example, each RS of theone or more second RSs may be identified by a respective one RS-specificindex of the RS-specific indices. In an example, a first RS of the oneor more second RSs may be identified by a first RS-specific index of theRS-specific indices. In an example, a second RS of the one or moresecond RSs may be identified by a second RS-specific index of theRS-specific indices.

In an example, at least one RS of the one or more second RSs may beconfigured/transmitted on/in the first cell. In an example, at least oneRS of the one or more second RSs may be configured/transmitted on/in thesecond cell. In an example, at least one RS of the one or more secondRSs may be configured/transmitted on/in at least one of the one or moresecondary cells. In an example, configuring the at least one RS of theone or more second RSs on the first cell and/or the at least one of theone or more secondary cells may save overhead and save complexity of thewireless device for tracking a high number of RSs.

In an example, at least one RS of the one or more second RSs may beconfigured/transmitted on/in the first cell. In an example, the secondcell and the first cell may share the at least one RS based on operatingin intra-band and/or QCL-ed (e.g., cross-carrier QCL) and/or based onsharing similar channel characteristics (e.g., Doppler spread, spatialfilter, etc.).

In an example, at least one RS of the one or more second RSs may beconfigured/transmitted on/in the second cell.

In an example, at least one RS of the one or more second RSs may beconfigured/transmitted on/in the at least one of the one or moresecondary cells. In an example, the second cell and the at least one ofthe one or more secondary cells may share the at least one RS based onoperating in intra-band and/or QCL-ed (e.g., cross-carrier QCL) and/orbased on sharing similar channel characteristics (e.g., Doppler spread,spatial filter, etc.).

In an example, the one or more configuration parameters may indicate asecond threshold (e.g., provided by rsrp-ThresholdSSB in the IEBeamFailureRecoveryConfig) for a beam failure recovery procedure of thesecond cell (or the second downlink BWP). In an example, the wirelessdevice may use the second threshold in a candidate beam selection of thesecond cell (or the second downlink BWP).

In an example, the one or more configuration parameters may indicate abeam failure recovery timer (e.g., provided by beamFailureRecoveryTimerin the IE BeamFailureRecoveryConfig) for a beam failure recoveryprocedure of the second cell (or the second downlink BWP).

In an example, the base station may configure the second threshold in aBWP (e.g., UL BWP, DL BWP) of the first cell. In an example, the basestation may configure the beam failure recovery timer in a BWP (e.g., ULBWP, DL BWP) of the first cell.

In an example, the base station may configure the second threshold in aBWP (e.g., UL BWP, DL BWP, the second downlink BWP) of the second cell.In an example, the base station may configure the beam failure recoverytimer in a BWP (e.g., UL BWP, DL BWP, the second downlink BWP) of thesecond cell.

In an example, the base station may configure the second threshold in aBWP (e.g., UL BWP, DL BWP) of at least one of the one or more secondarycells. In an example, the base station may configure the beam failurerecovery timer in a BWP (e.g., UL BWP, DL BWP) of at least one of theone or more secondary cells.

In an example, the base station may not provide the wireless device withreference signals for a candidate beam selection. In an example, the oneor more configuration parameters may not indicate one or more second RSs(e.g., candidateBeamRSList provided in IE BeamFailureRecoveryConfig) forthe second downlink BWP of the second cell. In an example, the wirelessdevice may not assess the one or more second RSs to select a candidateRS among the one or more second RSs for a beam failure recoveryprocedure of the second downlink BWP of the second cell. In an example,the wireless device may not perform a candidate beam selection for abeam failure recovery procedure of the second downlink BWP of the secondcell based on not being configured with the one or more second RSs.

In an example, the one or more configuration parameters may not indicatea second threshold (e.g., provided by rsrp-ThresholdSSB in the IEBeamFailureRecoveryConfig) for a beam failure recovery procedure of thesecond cell (or the second downlink BWP). In an example, the wirelessdevice may not perform a candidate beam selection for a beam failurerecovery procedure of the second downlink BWP of the second cell basedon not being configured with the second threshold.

In an example, the one or more configuration parameters may indicate asearch space set (e.g., provided by recoverySearchSpaceID in the IEBeamFailureRecoveryConfig). In an example, the search space set may belinked/associated with a control resource set (coreset). In an example,the search space set may indicate the coreset. In an example, thewireless device may monitor the coreset for a beam failure recoveryprocedure of the second cell (or of the second downlink BWP). In anexample, the base station may configure the coreset on the first cell.In an example, the base station may configure the coreset on the secondcell. In an example, the base station may configure the coreset on atleast one of the one or more secondary cells. In an example, thewireless device may monitor the search space set (e.g., linked to thecoreset) for a beam failure recovery procedure of the second downlinkBWP.

In an example, the second downlink BWP may be an active downlink BWP ofthe second cell. In an example, a physical layer in the wireless devicemay assess a first radio link quality of the one or more first RSs (fora beam failure detection of the second downlink BWP). The physical layermay provide a BFI indication to a higher layer (e.g. MAC) of thewireless device when the first radio link quality is worse (e.g., higherBLER, lower L1-RSRP, lower L1-SINR) than the first threshold.

In an example, the higher layer (e.g., MAC) of the wireless device mayincrement BFI_COUNTER by one in response to the physical layer providingthe BFI indication (e.g., at time T, 2T, 5T in FIG. 18). The BFI_COUNTERmay be a counter for a BFI indication. The wireless device may initiallyset the BFI_COUNTER to zero.

In an example, based on the incrementing the BFI_COUNTER, theBFI_COUNTER may be equal to or greater than the maximum BFI counter(e.g., beamFailureInstanceMaxCount). In an example, the wireless devicemay detect a beam failure of the second downlink BWP of the second cellbased on the BFI_COUNTER being equal to or greater than the maximum BFIcounter (time T1 in FIG. 19). In an example, the wireless device mayinitiate a beam failure recovery (BFR) procedure for the second downlinkBWP of the second cell based on the detecting the beam failure of thesecond downlink BWP (time T1 in FIG. 19). In an example, based on theinitiating the BFR procedure, the wireless device, if configured, maystart the beam failure recovery timer.

In an example, based on the initiating the BFR procedure, the wirelessdevice may initiate a candidate beam selection for the beam failurerecovery procedure (time T1 in FIG. 19). In an example, the wirelessdevice may initiate a candidate beam selection before initiating thebeam failure recovery procedure (e.g., before time T1 in FIG. 19,between time T0 and T1 in FIG. 19). In an example, the wireless devicemay initiate a candidate beam selection before detecting the beamfailure (e.g., before time T1 in FIG. 19, between time T0 and T1 in FIG.19). In an example, the wireless device may initiate a candidate beamselection based on being configured with the one or more second RSs(time T0 in FIG. 19). In an example, the wireless device may performbeam failure detection and candidate beam selection in parallel. In anexample, the wireless device may perform the candidate beam selectionduring the (ongoing) beam failure recovery procedure. In an example, thecandidate beam selection may comprise selecting/identifying a candidateRS (e.g., CSI-RS, SS/PBCH blocks) in/among the one or more second RSs(with quality higher than the second threshold).

In an example, the wireless device may initiate the candidate beamselection for the beam failure recovery procedure before the initiatingthe BFR procedure. In an example, the wireless device may initiate acandidate beam selection for the beam failure recovery procedure beforethe detecting the beam failure of the second downlink BWP. In anexample, the wireless device may perform one or more measurements on theone or more second RSs in parallel with estimating a first radio linkquality of the one or more first RSs.

In an example, the initiating the candidate beam selection may compriserequesting, by the higher layer from the physical layer, one or moreindices (of the RS-specific indices, for example, periodic CSI-RSconfiguration indexes and/or the SSB indexes provided by the one or moreconfiguration parameters) associated with one or more candidate RSsamong the one or more second RSs and/or one or more candidatemeasurements (e.g., L1-RSRP measurements) of the one or more candidateRSs. In an example, each measurement of the one or more candidatemeasurements may be better (e.g. lower BLER or higher L1-RSRP or higherL1-SINR) than the second threshold (e.g., rsrp-ThresholdSSB).

In an example, in the candidate beam selection, the physical layer ofthe wireless device may perform one or more measurements (e.g. L1-RSRPmeasurement) for the one or more second RSs. In an example, the wirelessdevice may perform each measurement of one or more measurements for acandidate RS of the one or more second RSs. In an example, the physicallayer may perform a first measurement of the one or more measurementsfor a first RS of the one or more second RSs. In an example, thephysical layer may perform a second measurement of the one or moremeasurements for a second RS of the one or more second RSs. In anexample, the physical layer may perform a third measurement of the oneor more measurements for a third RS of the one or more second RSs, andso on.

In an example, based on the performing the one or more measurements, thewireless device may determine that the one or more candidatemeasurements, of the one or more measurements, of the one or morecandidate RSs, of the one or more second RSs, are better (e.g. lowerBLER or higher L1-RSRP or higher SINR) than the second threshold (e.g.,rsrp-ThresholdSSB). In an example, each candidate RS of the one or morecandidate RSs has a candidate measurement (e.g., L1-RSRP), of the one ormore candidate measurements, better than the second threshold. In anexample, the first measurement for the first RS may be better (higherL1-RSRP) than the second threshold. In an example, the secondmeasurement for the second RS may be better (higher L1-RSRP) than thesecond threshold. In an example, the third measurement for the third RSmay be worse (lower L1-RSRP) than the second threshold. The one or morecandidate RSs may comprise the first RS and the second RS based on thefirst measurement and second measurement being better than the secondthreshold and the third measurement being worse than the secondthreshold. Based on the request, by the higher layer from the physicallayer, the physical layer may provide the first measurement and a firstRS-specific index of the first RS and the second measurement and asecond RS-specific index of the second RS.

In an example, based on the request, the physical layer of the wirelessdevice may provide, to the higher layer (e.g., MAC) of the wirelessdevice, one or more indices of the one or more candidate RSs (e.g., thefirst RS, the second RS) and one or more candidate measurements (e.g.,the first measurement, the second measurement) of the one or morecandidate RSs.

In an example, in response to receiving the one or more indices and theone or more candidate measurements associated with the one or morecandidate RSs, the higher layer (e.g., MAC) of the wireless device mayselect a candidate RS among the one or more candidate RSs. The higherlayer may indicate the candidate RS to the physical layer of thewireless device. In an example, the candidate RS may be identified witha candidate RS index (e.g., periodic CSI-RS configuration indexes and/orthe SSB indexes provided by the one or more configuration parameters) ofthe RS-specific indices (or of one or more indices of the RS-specificindices).

In an example, the one or more configuration parameters may indicateuplink physical channels (e.g., PUCCH, PRACH, PUSCH). In an example, theuplink physical channels may comprise physical random-access channels(PRACH) resources. In an example, the uplink physical channels maycomprise physical uplink control channel (PUCCH) resources. In anexample, the uplink physical channels may comprise physical uplinkshared channel (PUSCH) resources.

In an example, the wireless device may use (or transmit via at least oneuplink physical channel of) the uplink physical channels for a beamfailure recovery procedure of the second cell. In an example, the uplinkphysical channels may be dedicated to the beam failure recoveryprocedure of the second cell. In an example, when the wireless deviceinitiates a second beam failure recovery procedure for a third cell ofthe one or more secondary cells, the wireless may not transmit via theuplink physical channels for the second beam failure recovery procedureof the third cell based on the uplink physical channels being dedicatedto the second cell.

In an example, the uplink physical channels may be shared for beamfailure recovery procedure(s) of the one or more secondary cells. In anexample, when the wireless device initiates a second beam failurerecovery procedure for a third cell of the one or more secondary cells,the wireless may transmit via the uplink physical channels for thesecond beam failure recovery procedure of the third cell based on theuplink physical channels being shared for the one or more secondarycells.

In an example, the uplink physical channels may be dedicated for a beamfailure recovery procedure. In an example, the wireless device maytransmit an uplink signal based on initiating a beam failure recoveryprocedure. When the uplink physical channels are dedicated for the beamfailure recovery procedure, the wireless device may transmit the uplinksignal via the uplink physical channels based on the uplink signal beingfor the beam failure recovery procedure. In an example, the wirelessdevice may not transmit a second uplink signal (e.g., SR) via the uplinkphysical channels for a procedure other than a beam failure recoveryprocedure. In an example, the wireless device may not transmit a seconduplink signal (e.g., SR) via the uplink physical channels for requestinguplink resources to transmit a transport block (e.g., uplink data,UL-SCH, etc.).

In an example, the uplink physical channels may not be dedicated for abeam failure recovery procedure. In an example, the uplink physicalchannels may be shared for a beam failure recovery procedure and anotherprocedure (e.g., scheduling request, random-access, etc.). In anexample, the wireless device may transmit an uplink signal via theuplink physical channels for a beam failure recovery procedure. In anexample, the wireless device may transmit a second uplink signal (e.g.,SR) via the uplink physical channels for requesting uplink resources totransmit a transport block (e.g., uplink data, UL-SCH, etc.).

In an example, the uplink physical channels may be one-to-one associatedwith the one or more secondary cells. In an example, the wireless devicemay perform beam failure detection for a cell of the one or moresecondary cells when the cell is active. Each cell of the one or moresecondary cells may be associated with a respective uplink physicalchannel of the uplink physical channels. In an example, a first cell ofthe one or more secondary cells may be associated with a first uplinkphysical channel of the uplink physical channels. Based on theassociation, the wireless device may transmit a first uplink signal(e.g., SR, BFRQ, preamble, UCI, MAC CE, aperiodic CSI-RS, and the like)via the first uplink physical channel for a first BFR procedure of thefirst cell. Based on receiving the first uplink signal, the base stationmay be aware of the first BFR procedure of the first cell. In anexample, a second cell of the one or more secondary cells may beassociated with a second uplink physical channel of the uplink physicalchannels. Based on the association, the wireless device may transmit asecond uplink signal via the second uplink physical channel for a secondBFR procedure of the second cell. Based on receiving the second uplinksignal, the base station may be aware of the second BFR procedure of thesecond cell.

In an example, the base station may configure the uplink physicalchannels on the first cell. In an example, the base station mayconfigure the uplink physical channels on the second cell. In anexample, the base station may configure the uplink physical channels ona third cell (e.g., SCell with PUCCH) of the one or more secondarycells. In an example, the third cell may be different from the secondcell (e.g., a third cell-specific index of the third cell is differentfrom a second cell-specific index of the second cell).

In an example, the uplink physical channels may be dedicated to the beamfailure recovery procedure of the second cell. In response to beingdedicated to the beam failure recovery procedure of the second cell,when the base station receives an uplink signal (e.g., preamble viaPRACH, beam failure recovery request (BFRQ) transmission via PUCCH,scheduling request (SR) via PUCCH, BFR MAC-CE via PUSCH) via at leastone uplink physical channel (e.g., PUSCH, PRACH or PUCCH) of the uplinkphysical channels, the base station may be informed of the beam failurerecovery procedure of the second cell.

In an example, the uplink physical channels may not be dedicated to thebeam failure recovery procedure. When a base station receives an uplinksignal (e.g., the SR) via at least one uplink physical channel (e.g.,PUCCH) of the uplink physical channels, the base station may notdistinguish whether the uplink signal is transmitted for a beam failurerecovery procedure or for requesting uplink shared channel (UL-SCH)resources for an uplink transmission.

In an example, the wireless device may transmit an uplink signal (e.g.,preamble via PRACH, beam failure recovery request (BFRQ) transmissionvia PUCCH, scheduling request (SR) via PUCCH, MAC-CE via PUSCH,aperiodic CSI-RS via PUSCH) via at least one uplink physical channel(e.g., PRACH or PUCCH or PUSCH) of the uplink physical channels based oninitiating the beam failure recovery procedure for the second cell (attime T2 in FIG. 19).

In an example, the one or more configuration parameters may indicate aresponse window for the second cell (or for the second downlink BWP ofthe second cell). In an example, the one or more configurationparameters may indicate a maximum transmission counter (e.g.,sr-TransMax, bfrq-TransMax, preambleTransMax) for the second cell (orfor the second downlink BWP of the second cell).

In an example, the one or more configuration parameters may comprise oneor more coresets for the second downlink BWP of the second cell. In anexample, the wireless device may monitor the one or more coresets priorto the initiating the BFR procedure. In an example, the wireless devicemay not monitor the coreset (e.g., dedicated for BFR procedure) prior tothe initiating the BFR procedure. In an example, the wireless device maymonitor the one or more coresets and the coreset during the BFRprocedure. In an example, the wireless device may prioritize the coresetover the one or more coresets during the BFR procedure. In an example,the prioritizing the coreset over the one or more coresets may comprisethat the wireless device monitors the coreset and depending on itscapability, the wireless device may monitor at least one coreset of theone or more coresets.

In an example, the wireless device may start the response window (e.g.,ra-responseWindow, sr-prohibit timer, bfrq-prohibit timer), for adownlink control information (e.g., an uplink grant, triggeringaperiodic CSI-RS) from the base station, based on the transmitting theuplink signal. In an example, the wireless device may monitor, for theDCI from the base station, at least one PDCCH in the one or morecoresets within the response window (or while the response window isrunning).

In an example, the wireless device may increment a transmission counter(e.g., preamble_transmission_counter, sr-counter, bfrq-counter) by onebased on the transmitting the uplink signal. In an example, the wirelessdevice may set the transmission counter to an initial value (e.g., zero,one) based on the initiating the BFR procedure. In an example, thewireless device may retransmit the uplink signal until the transmissioncounter reaches to the maximum transmission counter.

In an example, the response window may expire. In an example, thewireless device may not receive the DCI within the response window(e.g., before the response window expires). Based on the response windowexpiring and the transmission counter being lower than the maximumtransmission counter, the wireless device may retransmit the uplinksignal, via at least one uplink physical channel of the uplink physicalchannels, for the BFR procedure.

In an example, the transmission counter may be equal to or higher thanthe maximum transmission counter. Based on the transmission counterbeing equal to or higher than the maximum transmission counter, thewireless device may initiate a random-access procedure (e.g.,contention-based random-access procedure).

In an example, based on the transmission counter being equal to orhigher than the maximum transmission counter, the wireless device maystop/reset the beam failure recovery timer. In an example, based on thetransmission counter being equal to or higher than the maximumtransmission counter, the wireless device may reset BFI_COUNTER to zero.

In an example, the wireless device may receive the DCI from the basestation at time T3 in FIG. 19. In an example, the wireless device mayreceive the DCI from the base station within the response window at timeT3 in FIG. 19.

In an example, the DCI may indicate uplink resources. In an example, theuplink resources may comprise time resources. In an example, the uplinkresources may comprise frequency resources.

In an example, the DCI may comprise an uplink grant. The uplink grantmay indicate the uplink resources.

In an example, the DCI may trigger a CSI report (e.g., aperiodic CSIreport). In an example, the DCI may comprise a CSI request fieldtriggering the CSI report. In an example, the uplink resources may beassociated with the CSI report.

In an example, the wireless device may transmit a second uplink signal(e.g., PUSCH, transport block, aperiodic CSI-report, UCI, PUCCH, MAC-CE,etc.) via uplink resources indicated by the DCI (at time T4 in FIG. 19).

In an example, the second uplink signal may be a MAC-CE (e.g., BFRMAC-CE, PHR MAC-CE, BSR, and the like). In an example, the second uplinksignal may be a layer-1 report. In an example, the second uplink signalmay be a CSI report (e.g., aperiodic CSI report).

In an example, the second uplink signal may comprise/indicate the secondcell-specific index of the second cell.

In an example, the wireless device may select/identify a candidate RS(of the one or more second RSs) associated/identified with a candidateRS index of the RS-specific indices for the BFR procedure. In anexample, the wireless device may select/identify the candidate RSthrough/in the candidate beam selection. In an example, based onselecting/identifying the candidate RS, the second uplink signal mayindicate the candidate RS index of the candidate RS.

In an example, the wireless device may initiate a BFR procedure for acell identified with a cell-specific index. The wireless device may, forthe BFR procedure of the cell, select/identify a candidate RS identifiedwith a candidate RS index. In an example, the second uplink signal maycomprise the cell-specific index. In an example, the second uplinksignal may comprise the candidate RS index.

In an example, the wireless device may not identify a candidate RS inthe candidate beam selection prior to the (scheduled) uplink resourcesindicated by the DCI (e.g., before time T4 in FIG. 19).

In an example, based on assessing/measuring the one or more second RSsin the candidate beam selection, the wireless device may determine thata candidate RS, among the one or more second RSs, has not beenidentified prior to (scheduled) uplink resources indicated by the DCI(e.g., uplink grant).

In an example, in the candidate beam selection, the wireless device maymeasure/assess (e.g., perform one or more measurements (e.g. L1-RSRPmeasurement)) the one or more second RSs to select a candidate RS amongthe one or more second RSs for the beam failure recovery procedure ofthe second downlink BWP of the second cell. In an example, notidentifying the candidate RS in the candidate beam selection maycomprise that the wireless device may determine that each measurement(e.g. L1-RSRP measurement) of one or more measurements for a candidateRS of the one or more second RSs is worse (e.g. higher BLER or lowerL1-RSRP or lower SINR) than the second threshold. In an example, notidentifying the candidate RS in the candidate beam selection maycomprise that none of the one or more second RSs has a candidatemeasurement/quality (e.g. L1-RSRP measurement) better than the secondthreshold. In an example, not identifying the candidate RS in thecandidate beam selection may comprise that each candidate RS of the oneor more second RSs has a candidate measurement/quality (e.g. L1-RSRPmeasurement) worse than the second threshold.

In an example, based on not identifying the candidate RS in thecandidate beam selection prior to the (scheduled) uplink resources ofthe uplink grant, the wireless device may transmit the second uplinksignal with a reserved index (e.g., 0000, 1111, etc.) at time T4 in FIG.19. In an example, transmitting the second uplink signal with thereserved index may comprise that the second uplink signal maycomprise/indicate the reserved index. The wireless device may transmitthe second uplink signal with the reserved index instead of with thecandidate RS index based on not identifying the candidate RS.

In an example, the one or more configuration parameters may not indicateone or more second RSs (e.g., candidateBeamRSList provided in IEBeamFailureRecoveryConfig) for the second downlink BWP of the secondcell. In an example, when the wireless device receives the DCI, based onnot being configured with the one or more second RSs, the wirelessdevice may transmit the second uplink signal with a reserved index(e.g., time T4 in FIG. 19).

In an example, the one or more configuration parameters may not indicatea second threshold (e.g., provided by rsrp-ThresholdSSB in the IEBeamFailureRecoveryConfig) for a beam failure recovery procedure of thesecond cell (or the second downlink BWP). In an example, when thewireless device receives the DCI, based on not being configured with thesecond threshold, the wireless device may transmit the second uplinksignal with a reserved index (e.g., time T4 in FIG. 19).

In an example, the reserved index may be preconfigured. In an example,the reserved index may be fixed. In an example, the one or moreconfiguration parameters may indicate the reserved index. In an example,the wireless device may select (e.g., randomly) the reserved index. Thereserved index may be different from the RS-specific indices. In anexample, the RS-specific indices may not comprise the reserved index.

Based on receiving the second uplink signal with the reserved index, thebase station may determine that the wireless device has not identified acandidate RS in the candidate beam selection. In an example, the basestation may deactivate the second cell based on the determining. In anexample, the base station may initiate a beam management (e.g.,aperiodic beam management, aperiodic CSI-RS) for the second cell basedon the determining.

In an example, the one or more configuration parameters may indicate asecond response window for the second cell. In an example, the one ormore configuration parameters may indicate a second maximum transmissioncounter (e.g., sr-TransMax, bfrq-TransMax, preambleTransMax,PUSCH-TransMax) for the second cell.

In an example, the wireless device may start the second response window(e.g., ra-responseWindow, sr-prohibit timer, bfrq-prohibit timer), for abeam failure recovery response from the base station, based on thetransmitting the second uplink signal. In an example, the wirelessdevice may monitor, for the beam failure recovery response from the basestation, at least one PDCCH in the coreset (linked to the search spaceset) within the second response window (or while the second responsewindow is running) In an example, at least one DM-RS of the at least onePDCCH may be associated (e.g., QCL-ed) with the candidate RS. In anexample, the wireless device may monitor, for the beam failure recoveryresponse from the base station, at least one PDCCH in at least onecoreset of the one or more coresets within the second response window(or while the second response window is running) In an example, thewireless device may monitor, for the beam failure recovery response fromthe base station, at least one PDCCH in at least one coreset of the oneor more coresets based on the transmitting the second uplink signal.

In an example, the beam failure recovery response may comprise a seconddownlink control information (DCI) indicating an uplink grant (e.g., forthe second cell). In an example, the beam failure recovery response maycomprise a second DCI indicating a downlink assignment (e.g., for thesecond cell). In an example, the beam failure recovery response maycomprise a second downlink control information (DCI) indicating anACK/NACK for the second uplink signal. In an example, the second DCI maybe configured with CRC scrambled by a RNTI (e.g., C-RNTI, MCS-C-RNTI,CS-RNTI) of the wireless device. In an example, the second DCI may beaddressed to the RNTI.

In an example, the wireless device may increment a second transmissioncounter (e.g., preamble_transmission_counter, sr-counter, bfrq-counter)by one based on the transmitting the second uplink signal. In anexample, the wireless device may set the second transmission counter toan initial value (e.g., zero, one) based on the initiating the BFRprocedure. In an example, the wireless device may set the secondtransmission counter to an initial value (e.g., zero, one) based onreceiving the DCI (e.g., time T3 in FIG. 19).

In an example, the wireless device may retransmit the second uplinksignal for the BFR procedure until the second transmission counterreaches to the second maximum transmission counter.

In an example, the second response window may expire. In an example, thewireless device may not receive the beam failure recovery responsewithin the second response window (e.g., before the second responsewindow expires). Based on the second response window expiring and thesecond transmission counter being lower than the second maximumtransmission counter, the wireless device may retransmit an uplinksignal (e.g., preamble, PUSCH, BSR, etc.) for the BFR procedure.

In an example, the second transmission counter may be equal to or higherthan the second maximum transmission counter. Based on the secondtransmission counter being equal to or higher than the second maximumtransmission counter, the wireless device may initiate a random-accessprocedure (e.g., contention-based random-access procedure).

In an example, based on the second transmission counter being equal toor higher than the second maximum transmission counter, the wirelessdevice may stop/reset the beam failure recovery timer. In an example,based on the second transmission counter being equal to or higher thanthe second maximum transmission counter, the wireless device may resetBFI_COUNTER to zero.

In an example, the wireless device may complete the BFR procedure forthe second cell successfully based on receiving the beam failurerecovery response in the coreset (or in the search space set) within thesecond response window.

In an example, the wireless device may complete the BFR procedure forthe second cell successfully based on receiving the beam failurerecovery response.

In an example, the wireless device may receive the DCI from the basestation at time T3 in FIG. 19.

In an example, the wireless device may complete the BFR procedure basedon the receiving the DCI (e.g., time T3 in FIG. 19).

In an example, the wireless device may complete the BFR procedure basedon transmitting the second uplink signal via the uplink resourcesindicated by the DCI (at time T4 in FIG. 19).

In an example, based on the completing the beam failure recoveryprocedure, the wireless device may stop/reset the beam failure recoverytimer. In an example, based on the completing the beam failure recoveryprocedure, the wireless device may reset BFI_COUNTER to zero.

FIG. 20 shows an example of a beam failure recovery procedure as per anaspect of an embodiment of the present disclosure. FIG. 21 is a flowdiagram of the beam failure recovery procedure disclosed in FIG. 20.

In an example, a wireless device may receive one or more messages (e.g.,time T0 in FIG. 20). The one or more messages may comprise one or moreconfiguration parameters for a plurality of cells. The plurality ofcells may comprise a first cell and a second cell.

In an example, the one or more configuration parameters may indicate oneor more second RS s (e.g., candidateBeamRSList provided in IEBeamFailureRecoveryConfig, candidate reference signal list, the one ormore second RSs discussed in FIG. 19) for a beam failure recoveryprocedure of the second cell. In an example, the wireless device mayassess the one or more second RSs (e.g., Second RS, Fourth RS in FIG.20) to select/identify a candidate RS among the one or more second RSsfor the beam failure recovery procedure. In an example, one or morecandidate RSs (e.g., Second RS in FIG. 20) of the one or more second RSsmay be configured/transmitted on/in the first cell. In an example, oneor more candidate RSs (e.g., Second RS in FIG. 20) of the one or moresecond RSs may be configured/transmitted on/in an active BWP of thefirst cell.

In an example, at time T1 in FIG. 20, the wireless device may initiate abeam failure recovery procedure for the second cell based on detecting abeam failure (as discussed for time T1 in FIG. 19).

In an example, at time T2 in FIG. 20, the wireless device may completethe beam failure recovery procedure for the second cell (completing aBFR procedure discussed in FIG. 19).

In an example, the wireless device may initiate a first candidate beamselection for the beam failure recovery procedure (at time T1 in FIG.20, before time T1 in FIG. 20, between time T0 and T1 in FIG. 20, attime T0 in FIG. 20). In an example, the first candidate beam selectionmay comprise selecting/identifying a candidate RS (e.g., CSI-RS, SS/PBCHblocks) in/among the one or more second RSs (Second RS, Fourth RS inFIG. 20). In an example, the wireless device may assess the one or moresecond RSs to select the candidate RS among the one or more second RSsfor the beam failure recovery procedure. In an example, the one or morecandidate RSs of the first cell may comprise the candidate RS (Second RSin FIG. 20). In an example, the wireless device may select/identify thecandidate RS of the one or more candidate RSs in the first candidatebeam selection for the beam failure recovery procedure. In an example,the candidate RS may be configured/transmitted on/in the first cell. Inan example, the candidate RS may be configured/transmitted on/in anactive BWP of the first cell.

In an example, the wireless device may deactivate the first cell duringthe beam failure recovery procedure (e.g., between T1 and T2 in FIG.20). In an example, the one or more configuration parameters mayindicate an SCell deactivation timer for the first cell. In an example,the wireless device may deactivate the first cell based on an expiry ofthe SCell deactivation timer. In an example, the wireless device maydeactivate the first cell based on receiving a MAC CE deactivating thefirst cell.

In an example, the deactivating the first cell during the beam failurerecovery procedure may comprise that the wireless device deactivates theactive BWP of the first cell during the beam failure recovery procedure(e.g., between T1 and T2 in FIG. 20). In an example, the one or moreconfiguration parameters may indicate a BWP inactivity timer for thefirst cell. In an example, the wireless device may deactivate the activeBWP based on an expiry of the BWP inactivity timer. In an example, thewireless device may deactivate the active BWP based on receiving adownlink signal (e.g., DCI, RRC). The wireless device may switch fromthe active BWP to a second BWP, of the first cell, indicated by thedownlink signal (e.g., BWP index field).

In an example, based on the deactivating the first cell during the beamfailure recovery procedure, the wireless device may stop/abort the beamfailure recovery procedure.

In an example, when the wireless device selects/identifies the candidateRS configured/transmitted on/in the first cell, based on thedeactivating the first cell during the beam failure recovery procedure,the wireless device may stop/abort the beam failure recovery procedure.

In an example, based on the deactivating the first cell during the beamfailure recovery procedure, the wireless device may initiate a secondcandidate beam selection for the beam failure recovery procedure.

In an example, when the wireless device selects/identifies the candidateRS configured/transmitted on/in the first cell, based on thedeactivating the first cell during the beam failure recovery procedure,the wireless device may initiate a second candidate beam selection forthe beam failure recovery procedure.

In an example, the second candidate beam selection may compriseselecting/identifying a candidate RS in/among the one or more second RSsexcluding/except/other than the one or more candidate RSs (Fourth RS inFIG. 20). In an example, the wireless device may assess the one or moresecond RSs excluding/except/other than the one or more candidate RSs toselect the candidate RS among the one or more second RSsexcluding/except/other than the one or more candidate RSs for the beamfailure recovery procedure.

In an example, the wireless device may transmit a second uplink signalfor the beam failure recovery procedure (as discussed for time T4 inFIG. 19). In an example, based on the deactivating the first cell duringthe beam failure recovery procedure, the wireless device may notadd/include one or more candidate RS-specific indices of the one or morecandidate RSs of the first cell in the second uplink signal. In anexample, the second uplink signal may not comprise/indicate the one ormore candidate RS-specific indices of the one or more candidate RSs.

In an example, the wireless device may transmit a second uplink signalfor the beam failure recovery procedure (as discussed for time T4 inFIG. 19). In an example, based on the deactivating the first cell duringthe beam failure recovery procedure, the wireless device may notadd/include a candidate RS index of the candidate RS of the first cellin the second uplink signal. In an example, the second uplink signal maynot comprise/indicate the candidate RS index of the candidate RS basedon the deactivating the first cell during the beam failure recoveryprocedure.

FIG. 22A and FIG. 22B show examples of a beam failure recoveryconfiguration as per an aspect of an embodiment of the presentdisclosure.

In an example, a wireless device may receive one or more messages. Theone or more messages may comprise one or more configuration parametersfor a plurality of cells comprising a second cell.

In an example, in FIG. 22A, the one or more configuration parameters maycomprise an information element (IE) BeamFailureRecoveryConfig for asecond downlink BWP of the second cell. The IE BeamFailureRecoveryConfigmay comprise a candidate RS list (e.g., candidateRSList in FIG. 22A)comprising at least one candidate cell-RS list (e.g.,CandidateRSListperCell). A maximum number of the at least one candidatecell-RS list may be a number of the plurality of cells (e.g.,maxNrofServingCells in FIG. 22A). In an example, the at least onecandidate cell-RS list may indicate a cell-specific index (e.g.,servingCellIndex) of a cell of the plurality of cells. The cell may bedifferent from the second cell. The cell may be same as the second cell.In an example, the at least one candidate cell-RS list may indicate atleast one BWP-RS list (e.g., CandidateRSperBWP) for the cell. A maximumnumber of the at least one BWP-RS list may be a number of configuredBWPs (e.g., maxNrofBWPs in FIG. 22A) for the cell. In an example, the atleast one BWP-RS list may indicate a BWP specific index (e.g., BWP-Id inFIG. 22A) of a BWP of the configured BWPs of the cell. In an example,the at least one BWP-RS list may indicate at least one RS (e.g., RSListin FIG. 22A) for the BWP. A maximum number of the at least one RS may bea maximum number of configured RSs for the BWP (e.g.,maxNrofCandidateBeamsperBWP in FIG. 22A). In an example, the at leastone RS may comprise an SSB indicated by SSB-index. In an example, the atleast one RS may comprise an CSI-RS indicated by NZP-CSI-RS-ResourceId.

In an example, in FIG. 22B, the one or more configuration parameters maycomprise an information element (IE) BeamFailureRecoveryConfig for asecond downlink BWP of the second cell. The IE BeamFailureRecoveryConfigmay comprise a candidate RS list (e.g., candidateRSList in FIG. 22B)comprising at least one candidate cell-RS list (e.g.,CandidateRSListperCell). A maximum number of the at least one candidatecell-RS list may be a number of the plurality of cells (e.g.,maxNrofServingCells in FIG. 22B). In an example, the at least onecandidate cell-RS list may indicate a cell-specific index (e.g.,servingCellIndex) of a cell of the plurality of cells. The cell may bedifferent from the second cell. The cell may be same as the second cell.In an example, the at least one candidate cell-RS list may indicate atleast one RS (e.g., RSList in FIG. 22B). A maximum number of the atleast one RS may be a maximum number of configured RSs (e.g.,maxNrofCandidateBeamsperCell in FIG. 22B) for the cell. In an example,the at least one RS may comprise an SSB indicated by SSB-index. In anexample, the at least one RS may comprise an CSI-RS indicated byNZP-CSI-RS-ResourceId.

FIG. 23 shows an example of a beam failure recovery procedure as per anaspect of an embodiment of the present disclosure. FIG. 24 is a flowdiagram of the beam failure recovery procedure disclosed in FIG. 23.

In an example, a wireless device may receive one or more messages (timeT0 in FIG. 23). The one or more messages may comprise one or moreconfiguration parameters of a plurality of cells. In an example, theplurality of cells may comprise a first cell and a second cell. In anexample, the plurality of cells may comprise a third cell.

In an example, the one or more configuration parameters may comprise aninformation element (IE) BeamFailureRecoveryConfig for a second downlinkBWP of the second cell. The IE BeamFailureRecoveryConfig may comprise acandidate RS list (e.g., candidateRSList in FIG. 22B) for the seconddownlink BWP of the second cell. The candidate RS list may comprise oneor more second RSs for the second downlink BWP of the second cell. Thecandidate RS list may indicate at least one candidate cell-RS listcomprising a first candidate cell-RS list, a second candidate cell-RSlist and a third candidate cell-RS list. The first candidate cell-RSlist may indicate a first cell-specific index of the first cell and atleast one first RS. In an example, in FIG. 23, at least one first RS maycomprise a first reference signal (RS-1) of a first downlink BWP (FirstBWP in FIG. 23) of the first cell, a second RS (RS-2) of the firstdownlink BWP, and a third RS (RS-3) of a third downlink BWP (Third BWPin FIG. 23) of the first cell. The second candidate cell-RS list mayindicate a second cell-specific index of the second cell and at leastone second RS. In an example, in FIG. 23, at least one second RS maycomprise a fourth RS (RS-4) and a fifth RS (RS-5) of the second downlinkBWP (Second BWP in FIG. 23) of the second cell. The third candidatecell-RS list may indicate a third cell-specific index of the third celland at least one third RS. In an example, in FIG. 23, at least one thirdRS may comprise a sixth RS (RS-6) of a fourth downlink BWP (Fourth BWPin FIG. 23) of the third cell and a seventh RS (RS-7) of a fifthdownlink BWP (Fifth BWP in FIG. 23) of the third cell.

In an example, the wireless device may activate the first downlink BWPof the first cell at a first time (e.g., symbol, slot, subframe, etc.).In an example, the activating the first downlink BWP may comprise thatthe wireless device may set the first downlink BWP as a first active BWPof the first cell. In an example, the wireless device may activate thesecond downlink BWP of the second cell at a second time (e.g., symbol,slot, subframe, etc.). In an example, the activating the second downlinkBWP may comprise that the wireless device may set the second downlinkBWP as a second active BWP of the second cell. In an example, thewireless device may activate the fourth downlink BWP of the third cellat a third time (e.g., symbol, slot, subframe, etc.). In an example, theactivating the third downlink BWP may comprise that the wireless devicemay set the third downlink BWP as a third active BWP of the third cell.

In an example, the first time and the second time may be different. Inan example, the first time and the second time may be the same. In anexample, the first time and the third time may be different. In anexample, the first time and the third time may be the same. In anexample, the third time and the second time may be different. In anexample, the third time and the second time may be the same.

In an example, the wireless device may be active on the first downlinkBWP of the first cell, the second downlink BWP of the second cell andthe fourth downlink BWP of the third cell (e.g., at time T1 in FIG. 23).Based on being active on the first downlink BWP, the second downlink BWPand the fourth downlink BWP, the wireless device may, in a candidatebeam selection for a beam failure recovery procedure of the seconddownlink BWP of the second cell, assess/measure the first RS and thesecond RS transmitted in the first downlink BWP, the fourth RS and thefifth RS transmitted in the second downlink BWP and the sixth RStransmitted in the fourth downlink BWP.

In an example, the wireless device may be inactive on the third downlinkBWP of the first cell and the fifth downlink BWP of the third cell(e.g., at time T1 in FIG. 23). Based on being inactive on the thirddownlink BWP and the fifth downlink BWP, the wireless device may not, ina candidate beam selection for a beam failure recovery procedure of thesecond downlink BWP of the second cell, assess/measure the third RStransmitted in the third downlink BWP and the seventh RS transmitted inthe fifth downlink BWP.

In an example, the wireless device may switch from the first downlinkBWP to the third downlink BWP for the first cell (at time T2 in FIG.23). In an example, based on the switching, the wireless device may beactive on the third downlink BWP of the first cell, the second downlinkBWP of the second cell and the fourth downlink BWP of the third cell(e.g., at time T2 in FIG. 23). Based on being active on the thirddownlink BWP, the second downlink BWP and the fourth downlink BWP, thewireless device may, in a candidate beam selection for a beam failurerecovery procedure of the second downlink BWP of the second cell,assess/measure the third RS transmitted in the third downlink BWP, thefourth RS and the fifth RS transmitted in the second downlink BWP andthe sixth RS transmitted in the fourth downlink BWP.

In an example, the wireless device may switch from the first downlinkBWP to the third downlink BWP for the first cell (at time T2 in FIG.23). In an example, based on the switching, the wireless device may beinactive on the first downlink BWP of the first cell and the fifthdownlink BWP of the third cell (e.g., at time T2 in FIG. 23). Based onbeing inactive on the first downlink BWP and the fifth downlink BWP, thewireless device may not, in a candidate beam selection for a beamfailure recovery procedure of the second downlink BWP of the secondcell, assess/measure the first RS and the second RS transmitted in thefirst downlink BWP and the seventh RS transmitted in the fifth downlinkBWP.

In an example, the wireless device may deactivate the third cell (attime T3 in FIG. 23). In an example, the one or more configurationparameters may indicate an SCell deactivation timer for the third cell.In an example, the wireless device may deactivate the third cell basedon an expiry of the SCell deactivation timer. In an example, thewireless device may deactivate the third cell based on receiving a MACCE deactivating the third cell.

In an example, based on the deactivating the third cell, the wirelessdevice may be active on the third downlink BWP of the first cell and thesecond downlink BWP of the second cell (e.g., at time T3 in FIG. 23).Based on being active on the third downlink BWP and the second downlinkBWP, the wireless device may, in a candidate beam selection for a beamfailure recovery procedure of the second downlink BWP of the secondcell, assess/measure the third RS transmitted in the third downlink BWP,the fourth RS and the fifth RS transmitted in the second downlink BWP.

In an example, based on the deactivating the third cell, the wirelessdevice may be inactive on the first downlink BWP of the first cell, thefourth downlink BWP of the third cell and the fifth downlink BWP of thethird cell (e.g., at time T3 in FIG. 23). Based on being inactive on thefirst downlink BWP, the fourth downlink BWP and the fifth downlink BWP,the wireless device may not, in a candidate beam selection for a beamfailure recovery procedure of the second downlink BWP of the secondcell, assess/measure the first RS and the second RS transmitted in thefirst downlink BWP, the sixth RS transmitted in the fourth downlink BWPand the seventh RS transmitted in the fifth downlink BWP.

In an example, the one or more second RSs may comprise one or morecandidate RS s (RS-1, RS-2, RS-3 in FIG. 23) transmitted/configured onthe first cell. In an example, the first candidate cell-RS list maycomprise the one or more candidate RSs (RS-1, RS-2, RS-3 in FIG. 23). Inan example, the base station may configure the one or more candidate RSsfor a beam failure recovery procedure of the second cell. In an example,the one or more candidate RSs may comprise the first RS, the second RSand the third RS in FIG. 23.

In an example, the wireless device may determine ones of the one or morecandidate RSs transmitted/configured on a first active BWP of the firstcell. In an example, when the first downlink BWP is the first active BWPof the first cell, the wireless device may determine the first RS andthe second RS of the one or more candidate RSs as the ones of the one ormore candidate RSs. In an example, when the third downlink BWP is thefirst active BWP of the first cell, the wireless device may determinethe third RS of the one or more candidate RSs as the ones of the one ormore candidate RSs. In an example, based on the determining, thewireless device may measure/assess the ones of the one or more candidateRSs in a candidate beam selection for a beam failure recovery procedureof the second cell.

In an example, the one or more second RSs may be transmitted on theplurality of cells. In an example, in FIG. 23, the one or more secondRSs may comprise the first RS, the second RS and the third RStransmitted on the first cell; the fourth RS and the fifth RStransmitted on the second cell; and the sixth RS and the seventh RStransmitted on the third cell. In an example, the base station mayconfigure the one or more second RSs for a beam failure recoveryprocedure of the second cell.

In an example, the wireless device may determine ones of the one or moresecondary RSs transmitted/configured on active cells of the plurality ofcells. In an example, when the third cell is active, the wireless devicemay determine the sixth RS and/or the seventh RS of the one or moresecond RSs as the ones of the one or more secondary RSs. In an example,when the third cell is deactivated, the wireless device may notdetermine the sixth RS and/or the seventh RS of the one or more secondRSs as the ones of the one or more secondary RSs. In an example, whenthe second cell is active, the wireless device may determine the fourthRS and the fifth RS of the one or more second RSs as the ones of the oneor more secondary RSs. In an example, based on the determining, thewireless device may measure/assess the ones of the one or more secondaryRSs in a candidate beam selection for a beam failure recovery procedureof the second cell.

In an example, the wireless device may determine ones of the one or moresecondary RSs transmitted/configured on an active BWP of active cells ofthe plurality of cells. In an example, when the third cell is active andthe fourth downlink BWP of the third cell is active, the wireless devicemay determine the sixth RS of the one or more second RSs as the ones ofthe one or more secondary RSs. In an example, when the third cell isdeactivated or the fourth downlink BWP is deactivated, the wirelessdevice may not determine the sixth RS of the one or more second RSs asthe ones of the one or more secondary RSs.

In an example, a MAC layer of the wireless device may indicate aphysical layer of the wireless device the ones of the one or moresecondary RSs to measure/assess for a candidate beam selection.

FIG. 25 shows an example of a beam failure recovery procedure as per anaspect of an embodiment of the present disclosure.

In an example, a wireless device may receive one or more messages (e.g.,time T0 in FIG. 25). The one or more messages may comprise one or moreconfiguration parameters of a plurality of cells comprising a secondcell.

In an example, at time T1 in FIG. 25, the wireless device may detect abeam failure for the second cell (e.g., as discussed for time T1 in FIG.19). In an example, the wireless device may initiate a beam failurerecovery procedure for the second cell (or the second downlink BWP ofthe second cell) based on the detecting the beam failure.

In an example, the one or more configuration parameters may indicate oneor more second RSs for the second cell (or the second downlink BWP ofthe second cell). In an example, the wireless device may assess the oneor more second RSs to select a candidate RS among the one or more secondRSs for a beam failure recovery procedure of the second cell. In anexample, a candidate RS of the one or more second RSs may beconfigured/transmitted on/in the second cell. In an example, a candidateRS of the one or more second RSs may be configured/transmitted on/in acell of the plurality of cells. In an example, the cell may be differentfrom the second cell. In an example, the cell may be same as the secondcell.

In an example, the wireless device may initiate a candidate beamselection for the beam failure recovery procedure (as discussed for T1in FIG. 19). In an example, in the candidate beam selection, a physicallayer of the wireless device may perform one or more measurements (e.g.L1-RSRP measurement) for the one or more second RSs.

In an example, at time T2 in FIG. 25, the wireless device may transmitan uplink signal (e.g., preamble via PRACH, beam failure recoveryrequest (BFRQ) transmission via PUCCH, scheduling request (SR) viaPUCCH, MAC-CE via PUSCH, aperiodic CSI-RS via PUSCH) via at least oneuplink physical channel (e.g., PRACH or PUCCH or PUSCH) of uplinkphysical channels based on initiating the beam failure recoveryprocedure for the second cell (as discussed for time T2 in FIG. 19).

In an example, the wireless device may monitor, for a downlink controlinformation (e.g., an uplink grant, triggering aperiodic CSI-RS) fromthe base station, based on the transmitting the uplink signal. In anexample, the wireless device may receive the DCI from the base stationat time T3 in FIG. 25.

In an example, based on the receiving the DCI, the wireless device maystart assembling a medium access control protocol data unit (MAC PDU) ina first time (e.g., at time T4 in FIG. 25). In an example, the wirelessdevice may complete the assembling the MAC PDU in a second time (e.g.,at time T5 in FIG. 25). In an example, the wireless device may transmita second uplink signal (e.g., BFR MAC CE, Aperiodic CSI report, etc.)including/comprising the MAC PDU at time T6 in FIG. 25.

In an example, the wireless device may identify one or more candidateRSs among the one or more secondary RSs in the candidate beam selectionfor the beam failure recovery procedure. In an example, one or morecandidate measurements of the one or more candidate RSs may be better(e.g. lower BLER or higher L1-RSRP or higher SINR) than the secondthreshold (e.g., rsrp-ThresholdSSB). In an example, each candidate RS ofthe one or more candidate RSs has a candidate measurement (e.g.,L1-RSRP), of the one or more candidate measurements, better than thesecond threshold.

In an example, the wireless device may determine/select a candidate RS,of the one or more candidate RSs, transmitted/configured on an activeBWP of an active serving cell of the plurality of cells. In an example,the wireless device may determine/select the candidate RS prior to thestarting assembly of the MAC PDU (e.g., before time T4 in FIG. 25,between time T3 and time T4 in FIG. 25, at time T4 in FIG. 25). In anexample, the wireless device may determine/select the candidate RS whenstarting assembly of the MAC PDU (e.g., at time T4 in FIG. 25). In anexample, the one or more candidate RSs may comprise a first RS and asecond RS of a first downlink BWP of a first cell of the plurality ofcells, a fourth RS of the second downlink BWP of the second cell and asixth RS of a fourth downlink BWP of a third cell of the plurality ofcells in FIG. 23. In an example, prior to the starting assembly of theMAC PDU, the wireless device may determine that the first downlink BWPof the first cell is deactivated. Based on the determining, the wirelessdevice may select a candidate RS among the fourth RS of the seconddownlink BWP of the second cell and the sixth RS of the fourth downlinkBWP of the third cell in response to the second downlink BWP of thesecond cell and the fourth downlink BWP of the third cell being active.

In an example, prior to the starting assembly of the MAC PDU, thewireless device may determine that the third cell is deactivated. Basedon the determining, the wireless device may select a candidate RS amongthe fourth RS of the second downlink BWP of the second cell, the firstRS and the second RS of the first downlink BWP of the first cell inresponse to the second downlink BWP of the second cell and the firstdownlink BWP of the first cell being active.

In an example, the wireless device may not include a candidate RS indexof a candidate RS configured/transmitted in/on a deactivated BWP and/ora deactivated cell. In an example, the second uplink signal may notindicate a candidate RS index of a candidate RS configured/transmittedin/on a deactivated BWP and/or a deactivated cell.

In an example, an RS of the one or more second RSs may be configured fora cell of the plurality cells. In an example, an RS of the one or moresecond RSs may be configured for a BWP of a cell of the plurality cells.

In an example, the second uplink signal may indicate a candidate RSindex of the candidate RS. The candidate RS may betransmitted/configured on the active BWP of the active serving cell ofthe plurality of cells.

In an example, the wireless device may measure/assess one or more secondRSs transmitted/configured on a deactivated BWP and/or a deactivatedcell for a candidate beam selection. In an example, the wireless devicemay not measure/assess one or more second RSs transmitted/configured ona deactivated BWP and/or a deactivated cell for another purpose otherthan a candidate beam selection (e.g., radio link monitoring).

FIG. 26 shows an example of a beam failure recovery configuration as peran aspect of an embodiment of the present disclosure. FIG. 27 is a flowdiagram of the beam failure recovery procedure disclosed in FIG. 26.

The steps at time T0, T1, T2 and T3 in FIG. 26 are same as the steps inT0, T1, T2 and T3 in FIG. 25.

In an example, a wireless device may receive one or more messages (e.g.,time T0 in FIG. 26). The one or more messages may comprise one or moreconfiguration parameters of a plurality of cells comprising a secondcell.

In an example, at time T1 in FIG. 26, the wireless device may detect abeam failure for the second cell (e.g., as discussed for time T1 in FIG.19). In an example, the wireless device may initiate a beam failurerecovery procedure for the second cell based on the detecting the beamfailure.

In an example, the one or more configuration parameters may indicate oneor more second RSs for the second cell. In an example, the wirelessdevice may assess the one or more second RSs to select a candidate RSamong the one or more second RSs in a candidate beam selection for abeam failure recovery procedure of the second cell. In an example, oneor more candidate RSs of the one or more second RSs may betransmitted/configured on a first cell of the plurality of cells. In anexample, one or more candidate RSs of the one or more second RSs may betransmitted/configured on BWP of a first cell of the plurality of cells.

In an example, the wireless device may, in the candidate beamidentification for the beam failure recovery procedure of the secondcell, determine/select a candidate RS of the one or more candidate RSsof the one or more secondary RSs. In an example, the candidate RS may betransmitted on a first active BWP of the first cell. In an example, thecandidate RS may be transmitted on the first cell.

In an example, at time T2 in FIG. 26, the wireless device may transmitan uplink signal (e.g., preamble via PRACH, beam failure recoveryrequest (BFRQ) transmission via PUCCH, scheduling request (SR) viaPUCCH, MAC-CE via PUSCH, aperiodic CSI-RS via PUSCH) via at least oneuplink physical channel (e.g., PRACH or PUCCH or PUSCH) of uplinkphysical channels based on initiating the beam failure recoveryprocedure for the second cell (as discussed for time T2 in FIG. 19).

In an example, the wireless device may monitor, for a downlink controlinformation (e.g., an uplink grant, triggering aperiodic CSI-RS) fromthe base station, based on the transmitting the uplink signal. In anexample, the wireless device may receive the DCI from the base stationat time T3 in FIG. 26.

In an example, based on the receiving the DCI, the wireless device maystart, in a first time (e.g., at time T4 in FIG. 26), assembling amedium access control protocol data unit (MAC PDU) indicating acandidate RS index of the candidate RS. In an example, the wirelessdevice may complete the assembling the MAC PDU in a second time (e.g.,at time T5 in FIG. 26).

In an example, the wireless device may determine that deactivation ofthe first cell occurs after the starting the assembly of the MAC PDU andbefore transmitting the MAC PDU (e.g., between time T4 and time T6 inFIG. 26). In an example, the deactivation of the first cell may comprisedeactivation of the first active BWP of the first cell. In an example,the deactivation of the first cell may occur based on an expiry of SCelldeactivation timer of the first cell. In an example, the deactivation ofthe first cell may occur based on receiving a MAC CE deactivating thefirst cell. In an example, deactivation of the first active BWP of thefirst cell may occur based on an expiry of a BWP inactivity timer of thefirst cell. In an example, deactivation of the first active BWP of thefirst cell may occur based on receiving a downlink signal (e.g., DCI,RRC) triggering BWP switching for the first cell.

In an example, based on the determining that deactivation of the firstcell occurs after the starting the assembly of the MAC PDU and beforetransmitting the MAC PDU, the wireless device may drop the transmissionof the MAC PDU. In an example, based on the determining thatdeactivation of the first cell occurs after the starting the assembly ofthe MAC PDU and before transmitting the MAC PDU (or before completingthe assembly of the MAC PDU), the wireless device may stop assemblingthe MAC PDU. In an example, the wireless device start assembling asecond MAC PDU indicating a second candidate RS of the one or moresecondary RSs based on the stopping the assembly of the MAC PDU. In anexample, the second candidate RS may have a radio link quality (e.g.,candidate measurement) better (e.g. lower BLER or higher L1-RSRP orhigher L1-SINR) than the second threshold.

In an example, the wireless device may start the assembly of the secondMAC PDU when there is enough time for the (PUSCH) processing/assembly ofthe second MAC PDU between the stopping the assembly of the MAC PDU anda first symbol of uplink resources indicated by the DCI.

In an example, the wireless device may transmit second uplink signalcomprising the MAC PDU with the candidate RS index after the determiningthat deactivation of the first cell occurs after the starting theassembly of the MAC PDU and before transmitting the MAC PDU. In anexample, based on receiving the MAC PDU, the base station may trigger aCSI report (e.g., aperiodic CSI report) in response to determining thatthe candidate RS indicated by the candidate RS index is transmitted onthe (deactivated) first cell or the (deactivated) first active BWP ofthe first cell.

FIG. 28 shows an example of a beam failure recovery procedure as per anaspect of an embodiment of the present disclosure. FIG. 29 is a flowdiagram of the beam failure recovery procedure disclosed in FIG. 28.

In an example, a wireless device may receive one or more messages (e.g.,time T0 in FIG. 28). The one or more messages may comprise one or moreconfiguration parameters of a plurality of cells.

In an example, the wireless device may detect a beam failure for atleast two cells of the plurality of cells. In an example, the wirelessdevice may initiate a beam failure recovery procedure based on thedetecting the beam failure.

In an example, the wireless device may detect a first beam failure for afirst cell of the at least two cells at a first time. In an example, thewireless device may detect a second beam failure for a second cell ofthe at least two cells at a second time. In an example, the first timeand the second time may be different. In an example, the first time andthe second time may be the same. In an example, the wireless device mayinitiate a first beam failure recovery procedure for the first cellbased on the detecting the first beam failure. In an example, thewireless device may initiate a second beam failure recovery procedurefor the second cell based on the detecting the second beam failure.

In an example, at time T1 in FIG. 28, the wireless device may transmitan uplink signal (e.g., preamble via PRACH, beam failure recoveryrequest (BFRQ) transmission via PUCCH, scheduling request (SR) viaPUCCH, MAC-CE via PUSCH, aperiodic CSI-RS via PUSCH) via at least oneuplink physical channel (e.g., PRACH or PUCCH or PUSCH) of uplinkphysical channels based on initiating the beam failure recoveryprocedure. In an example, the wireless device may transmit the uplinksignal for the first beam failure recovery procedure of the first cell.In an example, the wireless device may transmit the uplink signal forthe second beam failure recovery procedure of the second cell. In anexample, the wireless device may transmit a first uplink signal for thefirst beam failure recovery procedure of the first cell at a third time.In an example, the wireless device may transmit a second uplink signalfor the second beam failure recovery procedure of the second cell at afourth time. In an example, the third time and the fourth time may bedifferent. In an example, the third time and the fourth time may be thesame. In an example, the wireless device may not transmit a seconduplink signal for the second beam failure recovery procedure of thesecond cell based on the transmitting the first uplink signal.

In an example, the wireless device may monitor, for a downlink controlinformation (e.g., an uplink grant, triggering aperiodic CSI-RS) fromthe base station, based on the transmitting the uplink signal. In anexample, the wireless device may receive the DCI from the base stationat time T2 in FIG. 28.

In an example, the wireless device may transmit a second uplink signal(e.g., BFR MAC CE, aperiodic CSI report) via uplink resources indicatedby the DCI (at time T4 in FIG. 28).

In an example, the wireless device may determine that a number of the atleast two cells is greater than a maximum number of cells (e.g., Nmax).In an example, the second uplink signal may not accommodate/indicatecell-specific indices of cells when a number of the cells is more thanthe maximum number of cells.

In an example, the maximum number of cells may be two. In an example,the plurality of cells may comprise a first cell identified with a firstcell-specific index, a second cell identified with a secondcell-specific index and a third cell identified with a thirdcell-specific index. When a wireless device, before transmitting thesecond uplink signal, detects a first beam failure for the first cell ina first time, a second beam failure for the second cell in a second timeand a third beam failure for the third cell in a third time, based onthe maximum number of cells being two, the wireless device may notindicate the first beam failure, the second beam failure and the thirdbeam failure via the second uplink signal. In an example, based on themaximum number of cells being two, the wireless device may indicate thefirst beam failure of the first cell and the second beam failure of thesecond cell via the second uplink signal. In an example, based on themaximum number of cells being two, the wireless device may indicate thefirst beam failure of the first cell and the third beam failure of thethird cell via the second uplink signal. In an example, based on themaximum number of cells being two, the wireless device may indicate thesecond beam failure of the second cell and the third beam failure of thethird cell via the second uplink signal.

In an example, the one or more configuration parameters may indicate themaximum number of cells. In an example, the maximum number of cells maybe fixed. In an example, the maximum number of cells may bepreconfigured.

In an example, based on the determining that the number of the at leasttwo cells is greater than the maximum number of cells, the wirelessdevice may select one or more cells among the at least two cells (timeT3 in FIG. 28). A number of the one or more cells may be equal to orless than the maximum number of cells.

In an example, based on the selecting the one or more cells, thewireless device may transmit the second uplink signal (at time T4 inFIG. 28). The second uplink signal may indicate the one or morecell-specific indices of the one or more cells.

In an example, the selecting the one or more cells may compriseselecting the one or more cells with the lowest cell-specific indicesamong at least two cell specific indices of the at least two cells. Inan example, the maximum number of cells may be two. In an example, thefirst cell-specific index may be lower than the second cell-specificindex and the third cell-specific index. In an example, the thirdcell-specific index may be lower than the second cell-specific index. Inan example, the wireless device may determine that the firstcell-specific index of the first cell and the third cell-specific indexof the third cell may be lowest (the maximum number of cells=2)cell-specific indices among the first cell-specific index of the firstcell, the second cell-specific index of the second cell and the thirdcell-specific index of the third cell. In an example, based on thedetermining, the wireless device may select the first cell and thirdcell as the one or more cells. The wireless device may transmit thesecond uplink signal indicating the first cell-specific index of thefirst cell and the third cell-specific index of the third cell based onthe selecting. The one or more cell-specific indices may comprise thefirst cell-specific index and the third cell-specific index based on theselecting.

In an example, the third cell-specific index may be lower than thesecond cell-specific index and the first cell-specific index. In anexample, the second cell-specific index may be lower than the firstcell-specific index. In an example, the wireless device may determinethat the second cell-specific index of the second cell and the thirdcell-specific index of the third cell may be lowest (the maximum numberof cells=2) cell-specific indices among the first cell-specific index ofthe first cell, the second cell-specific index of the second cell andthe third cell-specific index of the third cell. In an example, based onthe determining, the wireless device may select the second cell andthird cell as the one or more cells. The wireless device may transmitthe second uplink signal indicating the second cell-specific index ofthe second cell and the third cell-specific index of the third cellbased on the selecting. The one or more cell-specific indices maycomprise the second cell-specific index and the third cell-specificindex based on the selecting.

In an example, the selecting the one or more cells may compriseselecting the one or more cells with the highest cell-specific indicesamong at least two cell specific indices of the at least two cells. Inan example, the maximum number of cells may be two. In an example, thefirst cell-specific index may be higher than the second cell-specificindex and the third cell-specific index. In an example, the thirdcell-specific index may be higher than the second cell-specific index.In an example, the wireless device may determine that the firstcell-specific index of the first cell and the third cell-specific indexof the third cell may be highest (the maximum number of cells=2)cell-specific indices among the first cell-specific index of the firstcell, the second cell-specific index of the second cell and the thirdcell-specific index of the third cell. In an example, based on thedetermining, the wireless device may select the first cell and thirdcell as the one or more cells. The wireless device may transmit thesecond uplink signal indicating the first cell-specific index of thefirst cell and the third cell-specific index of the third cell based onthe selecting. The one or more cell-specific indices may comprise thefirst cell-specific index and the third cell-specific index based on theselecting.

In an example, the third cell-specific index may be higher than thesecond cell-specific index and the first cell-specific index. In anexample, the second cell-specific index may be higher than the firstcell-specific index. In an example, the wireless device may determinethat the second cell-specific index of the second cell and the thirdcell-specific index of the third cell may be highest (the maximum numberof cells=2) cell-specific indices among the first cell-specific index ofthe first cell, the second cell-specific index of the second cell andthe third cell-specific index of the third cell. In an example, based onthe determining, the wireless device may select the second cell andthird cell as the one or more cells. The wireless device may transmitthe second uplink signal indicating the second cell-specific index ofthe second cell and the third cell-specific index of the third cellbased on the selecting. The one or more cell-specific indices maycomprise the second cell-specific index and the third cell-specificindex based on the selecting.

In an example, the selecting the one or more cells may compriseselecting the one or more cells with the highest priorities among atleast two cell specific priorities of the at least two cells. In anexample, the maximum number of cells may be two. In an example, thefirst cell-specific priority may be higher than the second cell-specificpriority and the third cell-specific priority. In an example, the thirdcell-specific priority may be higher than the second cell-specificpriority. In an example, the wireless device may determine that thefirst cell-specific priority of the first cell and the thirdcell-specific priority of the third cell may be highest (the maximumnumber of cells=2) cell-specific priorities among the firstcell-specific priority of the first cell, the second cell-specificpriority of the second cell and the third cell-specific priority of thethird cell. In an example, based on the determining, the wireless devicemay select the first cell and third cell as the one or more cells. Thewireless device may transmit the second uplink signal indicating thefirst cell-specific index of the first cell and the third cell-specificindex of the third cell based on the selecting. The one or morecell-specific indices may comprise the first cell-specific index and thethird cell-specific index based on the selecting.

In an example, the third cell-specific priority may be higher than thesecond cell-specific priority and the first cell-specific priority. Inan example, the second cell-specific priority may be higher than thefirst cell-specific priority. In an example, the wireless device maydetermine that the second cell-specific priority of the second cell andthe third cell-specific priority of the third cell may be highest (themaximum number of cells=2) cell-specific priorities among the firstcell-specific priority of the first cell, the second cell-specificpriority of the second cell and the third cell-specific priority of thethird cell. In an example, based on the determining, the wireless devicemay select the second cell and third cell as the one or more cells. Thewireless device may transmit the second uplink signal indicating thesecond cell-specific index of the second cell and the thirdcell-specific index of the third cell based on the selecting. The one ormore cell-specific indices may comprise the second cell-specific indexand the third cell-specific index based on the selecting.

In an example, a cell with a highest priority may be the cell servingthe wireless device with an URLLC service. In an example, a cell with ahighest priority may be the cell serving/scheduling the wireless devicewith an urgent data/control information.

In an example, the selecting the one or more cells may compriseselecting the one or more cells with the earliest beam failure detectiontimes among at least two beam failure detection times of the at leasttwo cells. In an example, the maximum number of cells may be two. In anexample, the first time may be earlier (in time) than the second timeand the third time. In an example, the third time may be earlier thanthe second time. In an example, the wireless device may determine thatthe first time of the first beam failure detection of the first cell andthe third time of the third beam failure detection of the third cell maybe earliest (the maximum number of cells=2) times among the first timeof the first cell, the second time of the second cell and the third timeof the third cell. In an example, based on the determining, the wirelessdevice may select the first cell and third cell as the one or morecells. The wireless device may transmit the second uplink signalindicating the first cell-specific index of the first cell and the thirdcell-specific index of the third cell based on the selecting. The one ormore cell-specific indices may comprise the first cell-specific indexand the third cell-specific index based on the selecting.

In an example, the third time may be earlier than the second time andthe first time. In an example, the second time may be earlier than thefirst time. In an example, the wireless device may determine that thesecond time of the second cell and the third time of the third cell maybe earliest (the maximum number of cells=2) times among the first timeof the first cell, the second time of the second cell and the third timeof the third cell. In an example, based on the determining, the wirelessdevice may select the second cell and third cell as the one or morecells. The wireless device may transmit the second uplink signalindicating the second cell-specific index of the second cell and thethird cell-specific index of the third cell based on the selecting. Theone or more cell-specific indices may comprise the second cell-specificindex and the third cell-specific index based on the selecting.

In an example, the selecting the one or more cells may compriseselecting the one or more cells with the latest beam failure detectiontimes among at least two beam failure detection times of the at leasttwo cells. In an example, the maximum number of cells may be two. In anexample, the first time may be later (in time) than the second time andthe third time. In an example, the third time may be later than thesecond time. In an example, the wireless device may determine that thefirst time of the first beam failure detection of the first cell and thethird time of the third beam failure detection of the third cell may belatest (the maximum number of cells=2) times among the first time of thefirst cell, the second time of the second cell and the third time of thethird cell. In an example, based on the determining, the wireless devicemay select the first cell and third cell as the one or more cells. Thewireless device may transmit the second uplink signal indicating thefirst cell-specific index of the first cell and the third cell-specificindex of the third cell based on the selecting. The one or morecell-specific indices may comprise the first cell-specific index and thethird cell-specific index based on the selecting.

In an example, the third time may be later than the second time and thefirst time. In an example, the second time may be later than the firsttime. In an example, the wireless device may determine that the secondtime of the second cell and the third time of the third cell may belatest (the maximum number of cells=2) times among the first time of thefirst cell, the second time of the second cell and the third time of thethird cell. In an example, based on the determining, the wireless devicemay select the second cell and third cell as the one or more cells. Thewireless device may transmit the second uplink signal indicating thesecond cell-specific index of the second cell and the thirdcell-specific index of the third cell based on the selecting. The one ormore cell-specific indices may comprise the second cell-specific indexand the third cell-specific index based on the selecting.

FIG. 30 shows an example of a beam failure recovery procedure as per anaspect of an embodiment of the present disclosure.

In an example, a wireless device may receive one or more messages (e.g.,time T0 in FIG. 30). The one or more messages may comprise one or moreconfiguration parameters of a plurality of cells. The plurality of cellsmay comprise a first cell and a second cell.

In an example, at time T1 in FIG. 30, the wireless device may detect asecond beam failure for the second cell (e.g., as discussed for time T1in FIG. 19). In an example, the wireless device may initiate a secondbeam failure recovery procedure for the second cell based on thedetecting the second beam failure.

In an example, at time T2 in FIG. 30, the wireless device may transmitan uplink signal (e.g., preamble via PRACH, beam failure recoveryrequest (BFRQ) transmission via PUCCH, scheduling request (SR) viaPUCCH, MAC-CE via PUSCH, aperiodic CSI-RS via PUSCH) via at least oneuplink physical channel (e.g., PRACH or PUCCH or PUSCH) of uplinkphysical channels based on initiating the second beam failure recoveryprocedure for the second cell (as discussed for time T2 in FIG. 19). Theone or more configuration parameters may indicate the uplink physicalchannels.

In an example, the wireless device may monitor, for a downlink controlinformation (e.g., an uplink grant, triggering aperiodic CSI-RS) fromthe base station, based on the transmitting the uplink signal. In anexample, the wireless device may receive the DCI from the base stationat time T3 in FIG. 30.

In an example, based on the receiving the DCI, the wireless device maystart, in a first time (e.g., at time T4 in FIG. 30), assembling amedium access control protocol data unit (MAC PDU). In an example, thewireless device may complete the assembling the MAC PDU in a second time(e.g., at time T5 in FIG. 30).

In an example, based on the completing the assembling the MAC PDU, thewireless device may transmit a second uplink signal (e.g., BFR MAC CE,Aperiodic CSI report, etc.) including the MAC PDU at time T6 in FIG. 30.In an example, the second uplink signal may indicate a secondcell-specific index of the second cell.

In an example, the wireless device may detect a first beam failure forthe first cell. In an example, the wireless device may initiate a firstbeam failure recovery procedure for the first cell based on thedetecting the first beam failure.

In an example, the wireless device may determine that the detecting thefirst beam failure occurs after the starting assembly of the MAC PDU andbefore the transmitting the MAC PDU (e.g., Case-2 in FIG. 30, betweentime T4 and time T6 in FIG. 30). Based on the determining, the wirelessdevice may complete the second beam failure recovery procedure of thesecond cell based on transmitting the second uplink signal (e.g., MACPDU). Based on the determining, the wireless device may continueperforming the first beam failure recovery procedure of the first cellafter transmitting the second uplink signal (e.g., MAC PDU). In anexample, the second uplink signal may not indicate a first cell-specificindex of the first cell based on detecting the first beam failure afterthe starting assembly of the MAC PDU.

In an example, the continuing performing the first beam failure recoveryprocedure may comprise the steps discussed at time T2, T3 and T4 of FIG.19. In an example, the continuing performing the first beam failurerecovery procedure may comprise transmitting an uplink signal (e.g.,preamble via PRACH, beam failure recovery request (BFRQ) transmissionvia PUCCH, scheduling request (SR) via PUCCH, MAC-CE via PUSCH,aperiodic CSI-RS via PUSCH) via at least one uplink physical channel(e.g., PRACH or PUCCH or PUSCH) of uplink physical channels (e.g., T2 inFIG. 19). In an example, the continuing performing the first beamfailure recovery procedure may comprise monitoring for a DCI (e.g., anuplink grant, triggering aperiodic CSI-RS) from the base station, basedon the transmitting the uplink signal (e.g., T3 in FIG. 19). In anexample, the continuing performing the first beam failure recoveryprocedure may comprise performing a candidate beam selection. In anexample, the wireless device may assess/measure one or more second RSs(indicated by the one or more configuration parameters for the firstcell) in a candidate beam selection. In an example, the continuingperforming the first beam failure recovery procedure may comprisetransmitting a second uplink signal via uplink resources indicated bythe DCI for the first beam failure recovery procedure. In an example,the continuing performing the first beam failure recovery procedure maycomprise monitoring for a beam failure recovery response (e.g., secondDCI, uplink grant, downlink assignment, ACK, NACK) for the second uplinksignal.

In an example, the wireless device may determine that the detecting thefirst beam failure occurs before/prior to the starting assembly of theMAC PDU (e.g., Case-1 in FIG. 30, between time T1 and time T4 in FIG.30, before time T4, before time T3, before time T2, etc.). Based on thedetermining, the wireless device may complete the second beam failurerecovery procedure of the second cell and the first beam failurerecovery procedure of the first cell based on transmitting the seconduplink signal (e.g., MAC PDU). In an example, the second uplink signalmay indicate the first cell-specific index of the first cell based ondetecting the first beam failure before/prior to the starting assemblingthe MAC PDU. In an example, the second uplink signal may indicate thesecond cell-specific index of the second cell.

In an example, the wireless device may stop transmitting the uplinksignal (e.g., preamble via PRACH, beam failure recovery request (BFRQ)transmission via PUCCH, scheduling request (SR) via PUCCH, MAC-CE viaPUSCH, aperiodic CSI-RS via PUSCH) for the first beam failure recoveryprocedure based on the completing the first beam failure recoveryprocedure.

In an example, a wireless device may detect a beam failure for asecondary cell (SCell). The wireless device may trigger a beam failurerecovery for the SCell based on the detecting the beam failure. Thewireless device may trigger transmission of a scheduling request (SR)based on triggering the beam failure recovery. The wireless device maytrigger transmission of the SR to indicate the beam failure recovery ofthe SCell. For example, the wireless device may receive, e.g., from abase station, an uplink grant based on the transmission of the SR. Thewireless device may transmit a beam failure recovery medium accesscontrol control element (BFR MAC-CE) indicating the beam failurerecovery of the SCell via an uplink resource indicated by the uplinkgrant. The BFR MAC-CE may comprise a serving cell index of the SCelland/or a candidate beam of the SCell to indicate the beam failurerecovery of the SCell.

In implementation of the legacy behavior, when the wireless devicereceives an uplink grant in response to the transmission of the SR forthe beam failure recovery, the wireless device experiences a delay fromthe time the wireless device detects a beam failure until the wirelessdevice transmits BFR MAC-CE (e.g., between time T1 and T6 for the BFRprocedure of the second cell in FIG. 30). Transmitting the SR andtransmitting a BFR MAC CE in an uplink grant (received in response tothe transmission of the SR) for the beam failure recovery may increaselatency of completing the beam failure recovery in some examplescenarios. Implementation of existing embodiments results in increasedlatency. A prolonged beam failure recovery may lead to reduced datarates and/or increased power consumption. Increased latency may resultin declaring a radio link failure (RLF). The wireless device may loseconnection with the base station based on the declaring the RLF. Thewireless device may re-establish connection with the base station basedon the declaring the RLF. Example embodiments improve/enhance a beamfailure recovery procedure when the beam failure recovery is triggeredprior to an assembling of a MAC PDU.

In an example embodiment, before receiving an uplink grant in responseto transmission of the SR, the wireless device may assemble and transmita MAC PDU (e.g., at time T2 in FIG. 31). In an example embodiment, basedon the beam failure recovery being triggered prior to the assembling ofthe MAC PDU, the wireless device may multiplex the BFR MAC-CE in the MACPDU. The MAC PDU may comprise the BFR MAC-CE indicating the beam failureof the SCell. The wireless device may stop transmission of the SR basedon transmitting the MAC PDU comprising the BFR MAC-CE. The wirelessdevice may cancel the triggered SR based on transmitting the MAC PDUcomprising the BFR MAC CE. Transmitting the MAC PDU comprising the BFRMAC CE that indicates the beam failure recovery of the SCell may reducelatency of completing the beam failure recovery (e.g., reduce from T0-T3to T0-T2 in FIG. 31). The wireless device may complete the beam failurerecovery earlier compared to the transmission of the SR. Reducing thelatency of completing the beam failure recovery may reduce powerconsumption at the wireless device and/or the base station. The wirelessdevice may re-establish connection with the base station earlier. Thewireless device may reduce declaring RLF.

FIG. 31 shows an example of a beam failure recovery procedure as per anaspect of an embodiment of the present disclosure. According to anexample embodiment, a wireless device may trigger a beam failurerecovery (BFR) of a secondary cell at time T0. The wireless device maytrigger transmission of a scheduling request (SR) based on thetriggering the BFR at time T0. The wireless device may transmit a mediumaccess control protocol data unit (MAC PDU) at time T2. The wirelessdevice may determine that the MAC PDU comprises a BFR medium accesscontrol element (BFR MAC CE). The BFR MAC CE may comprise information ofthe BFR triggered prior to assembling of the MAC PDU (e.g., prior totime T1). The wireless device may stop a configured transmission of theSR based on the transmitting the MAC PDU comprising the BFR MAC CEcomprising the information of the BFR that is triggered prior to theassembling of the MAC PDU (e.g., at time T3).

According to various embodiments, a device such as, for example, awireless device, off-network wireless device, a base station, and/or thelike, may comprise one or more processors and memory. The memory maystore instructions that, when executed by the one or more processors,cause the device to perform a series of actions. Embodiments of exampleactions are illustrated in the accompanying figures and specification.Features from various embodiments may be combined to create yet furtherembodiments.

FIG. 32 is a flow diagram as per an aspect of an example embodiment ofthe present disclosure. At 3210, a wireless device may trigger a beamfailure recovery (BFR) of a secondary cell. At 3220, the wireless devicemay trigger transmission of a scheduling request (SR) based on thetriggering the BFR. At 3230, the wireless device may transmit a mediumaccess control protocol data unit (MAC PDU). At 3240, the wirelessdevice may determine that the MAC PDU comprises a BFR medium accesscontrol element (BFR MAC CE). The BFR MAC CE may comprise information ofthe BFR triggered prior to assembling of the MAC PDU. At 3250, thewireless device may stop a configured transmission of the SR based onthe transmitting the MAC PDU comprising the BFR MAC CE comprising theinformation of the BFR that is triggered prior to the assembling of theMAC PDU.

According to an example embodiment, a wireless device may trigger a beamfailure recovery (BFR) of a secondary cell. The wireless device maytrigger transmission of a scheduling request (SR) based on thetriggering the BFR. The wireless device may transmit a medium accesscontrol protocol data unit (MAC PDU). The wireless device may determinethat the MAC PDU comprises a BFR medium access control element (BFR MACCE). The BFR MAC CE may comprise information of the BFR triggered priorto assembling of the MAC PDU. The wireless device may stop a configuredtransmission of the SR based on the transmitting the MAC PDU comprisingthe BFR MAC CE comprising the information of the BFR that is triggeredprior to the assembling of the MAC PDU.

According to an example embodiment, the wireless device may triggertransmission of a second SR based on triggering a second BFR of a secondsecondary cell. According to an example embodiment, the wireless devicemay transmit the second SR.

According to an example embodiment, the transmitting the second SR maybe based on the triggering of the second BFR occurring after theassembling of the MAC PDU. According to an example embodiment, the BFRMAC CE may not comprise information of the second BFR triggered afterthe assembling of the MAC PDU.

According to an example embodiment, the transmitting the second SR maybe based on the BFR MAC CE not comprising information of the second BFRof the second secondary cell. According to an example embodiment, thetriggering of the second BFR may occur prior to the assembling of theMAC PDU.

According to an example embodiment, the wireless device may continue thesecond BFR. According to an example embodiment, the transmitting thesecond SR may be based on the continuing the second BFR.

According to an example embodiment, the transmitting of the second SRmay comprise transmitting the second SR via a physical uplink controlchannel (PUCCH). According to an example embodiment, the wireless devicemay receive one or more messages comprising one or more configurationparameters indicating the PUCCH for the second BFR of the secondsecondary cell.

According to an example embodiment, the stopping of the configuredtransmission of the SR may comprise completing the BFR of the secondarycell.

According to an example embodiment, the wireless device may receive adownlink control information (DCI) indicating an uplink grant. Accordingto an example embodiment, the assembling the MAC PDU may be based on thereceiving the DCI indicating the uplink grant. According to an exampleembodiment, the transmitting of the MAC PDU may comprise transmittingthe MAC PDU via an uplink resource indicated by the uplink grant.

According to an example embodiment, the BFR MAC CE comprising theinformation of the BFR may comprise the BFR MAC CE comprising a firstfield that indicates a first cell index of the secondary cell with theBFR. According to an example embodiment, the BFR MAC

CE comprising the information of the BFR may comprise the BFR MAC CEcomprising a second field that indicates a candidate reference signalindex indicating a candidate reference signal for the secondary cellwith the BFR.

According to an example embodiment, the wireless device may receive oneor more messages comprising one or more configuration parameters for thesecondary cell. The one or more configuration parameters may indicateone or more reference signals. The one or more configuration parametersmay indicate a radio link quality threshold. The one or moreconfiguration parameters may indicate a maximum beam failure instancecounter. According to an example embodiment, the wireless device maydetermine a beam failure instance based on assessing the one or morereference signals with radio quality lower than the radio link qualitythreshold. According to an example embodiment the triggering the BFR maybe based on a number of beam failure instances reaching to the maximumbeam failure instance counter.

According to an example embodiment, a wireless device may assemble amedium access control protocol data unit (MAC PDU). The wireless devicemay trigger a beam failure recovery (BFR) of a secondary cell. Thewireless device may trigger transmission of a scheduling request (SR)based on the triggering the BFR. The wireless device may transmit theMAC PDU. The wireless device may determine that the MAC PDU comprises aBFR medium access control element (BFR MAC CE). The BFR MAC CE maycomprise information of the BFR triggered prior to the assembling of theMAC PDU. The wireless device may stop a configured transmission of theSR based on the transmitting the MAC PDU and the MAC PDU comprising theBFR MAC CE comprising the information of the BFR that is triggered priorto the assembling of the MAC PDU.

According to an example embodiment, a wireless device may receive one ormore messages. The one or more messages may comprise one or moreconfiguration parameters of a plurality of cells. The plurality of cellsmay comprise a first cell and a second cell. The one or moreconfiguration parameters may indicate one or more candidate referencesignals (RSs) on the first cell for a beam failure recovery (BFR)procedure of the second cell. According to an example embodiment, thewireless device may initiate the BFR procedure for the second cell.According to an example embodiment, the wireless device may deactivatethe first cell during the BFR procedure. According to an exampleembodiment, the wireless device may abort the BFR procedure based on thedeactivating the first cell during the BFR procedure.

According to an example embodiment, a wireless device may receive one ormore messages. The one or more messages may comprise one or moreconfiguration parameters of a plurality of cells. The plurality of cellsmay comprise a first cell and a second cell. The one or moreconfiguration parameters may indicate candidate reference signals (RSs)on the first cell for a beam failure recovery (BFR) procedure of thesecond cell. According to an example embodiment, the wireless device maydetermine ones of the candidate RSs on an active bandwidth part (BWP) ofthe first cell. According to an example embodiment, the wireless devicemay measure the ones of the candidate RSs for the BFR procedure of thesecond cell.

Embodiments may be configured to operate as needed. The disclosedmechanism may be performed when certain criteria are met, for example,in a wireless device, a base station, a radio environment, a network, acombination of the above, and/or the like. Example criteria may bebased, at least in part, on for example, wireless device or network nodeconfigurations, traffic load, initial system set up, packet sizes,traffic characteristics, a combination of the above, and/or the like.When the one or more criteria are met, various example embodiments maybe applied. Therefore, it may be possible to implement exampleembodiments that selectively implement disclosed protocols.

A base station may communicate with a mix of wireless devices. Wirelessdevices and/or base stations may support multiple technologies, and/ormultiple releases of the same technology. Wireless devices may have somespecific capability(ies) depending on wireless device category and/orcapability(ies). A base station may comprise multiple sectors. When thisdisclosure refers to a base station communicating with a plurality ofwireless devices, this disclosure may refer to a subset of the totalwireless devices in a coverage area. This disclosure may refer to, forexample, a plurality of wireless devices of a given LTE or 5G releasewith a given capability and in a given sector of the base station. Theplurality of wireless devices in this disclosure may refer to a selectedplurality of wireless devices, and/or a subset of total wireless devicesin a coverage area which perform according to disclosed methods, and/orthe like. There may be a plurality of base stations or a plurality ofwireless devices in a coverage area that may not comply with thedisclosed methods, for example, because those wireless devices or basestations perform based on older releases of LTE or 5G technology.

In this disclosure, “a” and “an” and similar phrases are to beinterpreted as “at least one” and “one or more.” Similarly, any termthat ends with the suffix “(s)” is to be interpreted as “at least one”and “one or more.” In this disclosure, the term “may” is to beinterpreted as “may, for example.” In other words, the term “may” isindicative that the phrase following the term “may” is an example of oneof a multitude of suitable possibilities that may, or may not, beemployed to one or more of the various embodiments.

If A and B are sets and every element of A is also an element of B, A iscalled a subset of B. In this specification, only non-empty sets andsubsets are considered. For example, possible subsets of B={cell1,cell2} are: {cell1}, {cell2}, and {cell1, cell2}. The phrase “based on”(or equally “based at least on”) is indicative that the phrase followingthe term “based on” is an example of one of a multitude of suitablepossibilities that may, or may not, be employed to one or more of thevarious embodiments. The phrase “in response to” (or equally “inresponse at least to”) is indicative that the phrase following thephrase “in response to” is an example of one of a multitude of suitablepossibilities that may, or may not, be employed to one or more of thevarious embodiments. The phrase “depending on” (or equally “depending atleast to”) is indicative that the phrase following the phrase “dependingon” is an example of one of a multitude of suitable possibilities thatmay, or may not, be employed to one or more of the various embodiments.The phrase “employing/using” (or equally “employing/using at least”) isindicative that the phrase following the phrase “employing/using” is anexample of one of a multitude of suitable possibilities that may, or maynot, be employed to one or more of the various embodiments.

The term configured may relate to the capacity of a device whether thedevice is in an operational or non-operational state. Configured mayalso refer to specific settings in a device that effect the operationalcharacteristics of the device whether the device is in an operational ornon-operational state. In other words, the hardware, software, firmware,registers, memory values, and/or the like may be “configured” within adevice, whether the device is in an operational or nonoperational state,to provide the device with specific characteristics. Terms such as “acontrol message to cause in a device” may mean that a control messagehas parameters that may be used to configure specific characteristics ormay be used to implement certain actions in the device, whether thedevice is in an operational or non-operational state.

In this disclosure, various embodiments are disclosed. Limitations,features, and/or elements from the disclosed example embodiments may becombined to create further embodiments within the scope of thedisclosure.

In this disclosure, parameters (or equally called, fields, orInformation elements: IEs) may comprise one or more information objects,and an information object may comprise one or more other objects. Forexample, if parameter (IE) N comprises parameter (IE) M, and parameter(IE) M comprises parameter (IE) K, and parameter (IE) K comprisesparameter (information element) J. Then, for example, N comprises K, andN comprises J. In an example embodiment, when one or more messagescomprise a plurality of parameters, it implies that a parameter in theplurality of parameters is in at least one of the one or more messages,but does not have to be in each of the one or more messages.

Furthermore, many features presented above are described as beingoptional through the use of “may” or the use of parentheses. For thesake of brevity and legibility, the present disclosure does notexplicitly recite each and every permutation that may be obtained bychoosing from the set of optional features. However, the presentdisclosure is to be interpreted as explicitly disclosing all suchpermutations. For example, a system described as having three optionalfeatures may be embodied in seven different ways, namely with just oneof the three possible features, with any two of the three possiblefeatures or with all three of the three possible features.

Many of the elements described in the disclosed embodiments may beimplemented as modules. A module is defined here as an element thatperforms a defined function and has a defined interface to otherelements. The modules described in this disclosure may be implemented inhardware, software in combination with hardware, firmware, wetware (i.e.hardware with a biological element) or a combination thereof, all ofwhich may be behaviorally equivalent. For example, modules may beimplemented as a software routine written in a computer languageconfigured to be executed by a hardware machine (such as C, C++,Fortran, Java, Basic, Matlab or the like) or a modeling/simulationprogram such as Simulink, Stateflow, GNU Octave, or LabVIEWMathScript.Additionally, it may be possible to implement modules using physicalhardware that incorporates discrete or programmable analog, digitaland/or quantum hardware. Examples of programmable hardware comprise:computers, microcontrollers, microprocessors, application-specificintegrated circuits (ASICs); field programmable gate arrays (FPGAs); andcomplex programmable logic devices (CPLDs). Computers, microcontrollersand microprocessors are programmed using languages such as assembly, C,C++ or the like. FPGAs, ASICs and CPLDs are often programmed usinghardware description languages (HDL) such as VHSIC hardware descriptionlanguage (VHDL) or Verilog that configure connections between internalhardware modules with lesser functionality on a programmable device. Theabove mentioned technologies are often used in combination to achievethe result of a functional module.

The disclosure of this patent document incorporates material which issubject to copyright protection. The copyright owner has no objection tothe facsimile reproduction by anyone of the patent document or thepatent disclosure, as it appears in the Patent and Trademark Officepatent file or records, for the limited purposes required by law, butotherwise reserves all copyright rights whatsoever.

While various embodiments have been described above, it should beunderstood that they have been presented by way of example, and notlimitation. It will be apparent to persons skilled in the relevantart(s) that various changes in form and detail can be made thereinwithout departing from the scope. In fact, after reading the abovedescription, it will be apparent to one skilled in the relevant art(s)how to implement alternative embodiments. Thus, the present embodimentsshould not be limited by any of the above described exemplaryembodiments.

In addition, it should be understood that any figures which highlightthe functionality and advantages, are presented for example purposesonly. The disclosed architecture is sufficiently flexible andconfigurable, such that it may be utilized in ways other than thatshown. For example, the actions listed in any flowchart may bere-ordered or only optionally used in some embodiments.

Further, the purpose of the Abstract of the Disclosure is to enable theU.S. Patent and Trademark Office and the public generally, andespecially the scientists, engineers and practitioners in the art whoare not familiar with patent or legal terms or phraseology, to determinequickly from a cursory inspection the nature and essence of thetechnical disclosure of the application. The Abstract of the Disclosureis not intended to be limiting as to the scope in any way.

Finally, it is the applicant's intent that only claims that include theexpress language “means for” or “step for” be interpreted under 35U.S.C. 112. Claims that do not expressly include the phrase “means for”or “step for” are not to be interpreted under 35 U.S.C. 112.

What is claimed is:
 1. A method comprising: triggering, by a wirelessdevice, transmission of a scheduling request (SR) based on triggering abeam failure recovery (BFR) of a secondary cell; and stopping aconfigured transmission of the SR based on transmitting a medium accesscontrol protocol data unit (MAC PDU) comprising a BFR medium accesscontrol control element (BFR MAC CE) comprising information of the BFR.2. The method of claim 1, further comprising triggering transmission ofa second SR based on triggering a second BFR of a second secondary cell.3. The method of claim 2, further comprising transmitting the second SR.4. The method of claim 3, wherein the transmitting the second SR isbased on the triggering of the second BFR occurring after assembling ofthe MAC PDU.
 5. The method of claim 4, wherein the BFR MAC CE does notcomprise information of the second BFR triggered after assembling of theMAC PDU.
 6. The method of claim 5, further comprising continuing thesecond BFR.
 7. The method of claim 6, wherein the transmitting thesecond SR is based on the continuing the second BFR.
 8. The method ofclaim 1, wherein the stopping the configured transmission of the SRcomprises completing the BFR of the secondary cell.
 9. The method ofclaim 1, wherein the BFR MAC CE comprising the information of the BFRcomprises that the BFR MAC CE comprises a first field indicating a firstcell index of the secondary cell with the BFR.
 10. The method of claim9, wherein the BFR MAC CE comprising the information of the BFRcomprises the BFR MAC CE comprising a second field indicating acandidate reference signal index indicating a candidate reference signalfor the secondary cell with the BFR.
 11. A wireless device comprising:one or more processors; and memory storing instructions that, whenexecuted by the one or more processors, cause the wireless device to:trigger transmission of a scheduling request (SR) based on triggering abeam failure recovery (BFR) of a secondary cell; and stop a configuredtransmission of the SR based on transmitting a medium access controlprotocol data unit (MAC PDU) comprising a BFR medium access controlcontrol element (BFR MAC CE) comprising information of the BFR.
 12. Thewireless device of claim 11, wherein the instructions, when executed bythe one or more processors, further cause the wireless device to triggertransmission of a second SR based on triggering a second BFR of a secondsecondary cell.
 13. The wireless device of claim 12, wherein theinstructions, when executed by the one or more processors, further causethe wireless device to transmit the second SR.
 14. The wireless deviceof claim 13, wherein the transmission of the second SR is based on thetriggering of the second BFR occurring after assembling of the MAC PDU.15. The wireless device of claim 14, wherein the BFR MAC CE does notcomprise information of the second BFR triggered after assembling of theMAC PDU.
 16. The wireless device of claim 15, wherein the instructions,when executed by the one or more processors, further cause the wirelessdevice to continue the second BFR.
 17. The wireless device of claim 16,wherein the transmission of the second SR is based on the continuationof the second BFR.
 18. The wireless device of claim 11, wherein thestopping of the configured transmission of the SR comprises completingthe BFR of the secondary cell.
 19. The wireless device of claim 11,wherein the BFR MAC CE comprising the information of the BFR comprisesthe BFR MAC CE comprising a first field indicating a first cell index ofthe secondary cell with the BFR.
 20. A system comprising: a basestation; and a wireless device comprising: one or more processors; andmemory storing instructions that, when executed by the one or moreprocessors, cause the wireless device to: receive, from the basestation, one or more configuration parameters indicating one or moreresources for a configured transmission of a scheduling request (SR);trigger transmission of the SR based on triggering a beam failurerecovery (BFR) of a secondary cell; and stop the configured transmissionof the SR based on transmitting a medium access control protocol dataunit (MAC PDU) comprising a BFR medium access control control element(BFR MAC CE) comprising information of the BFR.